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METAL OXIDE SUPPORTED CADMIUM SULFIDE
FOR
PHOTOCATALYTIC SYNTHESIS OF HOMOALLYLAMINES
Den Naturwissenschaftlichen Fakultäten
der Friedrich-Alexander-Universität Erlangen-Nürnberg
zur
Erlangung des Doktorgrades
vorgelegt von
Müge Aldemir
aus Izmir, Türkei
Als Dissertation genehmigt
von den Naturwissenschaftlichen Fakultäten
der Universität Erlangen-Nürnberg
Tag der mündlichen Prüfung: 16.02.2006
Vorsitzender der Promotionskommission: Prof. Dr. D.-P. Häder
Erstberichterstatter: Prof. Dr. H. Kisch
Zweitberichterstatter: Prof. Dr. D. Guldi
Die vorliegende Arbeit wurde von Januar 2003 bis November 2005 am Institut für
Anorganische Chemie der Friedrich-Alexander Universität Erlangen-Nürnberg unter
Anleitung von Herrn Prof. Dr. Horst Kisch durchgeführt.
I gratefully thank my doctoral father Prof. Dr. H. Kisch for offering me the opportunity to
make my Ph. D. in Germany, in the interesting field of semiconductor photocatalysis and
for instructive discussions during my work.
I would like to thank Deutsche Forschungsgemeinschaft for the fellowship within the
Graduiertenkolleg “Homogener und Heterogener Electronentransfer” and Prof. Dr. U.
Nickel for collaboration within the Graduiertenkolleg.
I thank Dr. M. Moll, Dr. S. Y. Shaban, Dr. K. Hein and S. Kasper for the NMR, Dr. C.
Damm for the time resolved photocharge, M. Bachmüller for the mass spectroscopy, S.
Kammerer for the XRD measurements, C. Wronna for the elemental analysis, R. Müller
for TGA and BET measurements, and Dr. G. Frank for the TEM analysis. I am also
thankful to Dr. F. W. Heinemann for the X-ray crystal structure determinations and Dr. J.
Sutter for his assistance regarding computer problems.
To Dr. G. Burgeth and Dr. M. Hopfner who are not only my friends but also my
“teachers”, I am especially thankful for their sincerity, help, encouragement, and for always
reminding me to think optimistic in my hard times.
I am also grateful to S. Sperner and N. Mooren for being always there (in the Organic
Institute) for me and for their friendship.
I am deeply thankful to my sisters in Erlangen; Dr. O. Linnik and Dr. P. Pinto. They have
been tireless helping whenever I needed and there are no words to express my thanks to
them.
I am indebted to my parents who educated me to be self-confident and self-sufficient in any
case in the life, but also made me feel like I am never alone. I thank them for their belief in
me, endless affection and support.
And to my sister, my best friend Bilge. Even so far from, my happiness was bigger; my
sorrow was less whenever I shared with her.
Abbreviations
δ Chemical Shift
λ Wavelength [nm]
ν Frequency
Θ Diffraction Angle (XRD)
τ Lifetime
A Acceptor
BET Brunauer-Emmet-Teller
br Broad
CB Conduction Band
COSY Correlation Spectroscopy
CV Cyclic Voltammetry
d Doublet (NMR), Interplanar Spacing in a Crystal (XRD)
D Donor
DRS Diffuse Reflectance Spectroscopy
E Energy
E° Redox Potential
Ebg Band-gap Energy
EF Fermi Level
nEF* Quasi-Fermi Level of Electrons
pEF* Quasi-Fermi Level of Holes
Eox Oxidation Potential
Ered Reduction Potential
FD Field Desorption (MS)
F(R∞) Kubbelka-Munk Function
FWHM Full-width of XRD Peak at Half-Maximum
h+ Hole in Valence Band
HETCOR Heteronuclear Correlation Spectroscopy
HPLC High Pressure Liquid Chromatography
HRTEM High Resolution Transmission Electron Microscopy
I Light Intensity
IFET Interfacial Electron Transfer
k Rate Constant
m Multiplet (NMR)
MS Mass Spectroscopy
MV2+ Methylviologen, N,N`-Dimethyl-4,4`-bipyridinium ion
P-EMF Photo-Electromotive Force
RT Room Temperature
s Second; Singlet (NMR)
S Scattering Coefficient
SEMSI Semiconductor Support Interaction
tR Retention Time
tr Triplet (NMR)
TEM Transmission Electron Microscopy
TLC Thin Layer Chromatography
TMS Tetramethylsilane
U Dember Voltage
VB Valence Band
W Width of Depletion Layer
XPS X-ray Photoelectron Spectroscopy
XRD X-ray-Diffractogram
Naming of Photocatalysts
CdS-A Unsupported CdS
Alumina Supported
10N 10% CdS/Al2O3(n) [10% wt of CdS supported on neutral alumina]
prepared in 10% NH3 solution
30N 30% CdS/Al2O3(n) [30% wt of CdS supported on neutral alumina]
prepared in 10% NH3 solution
50N 50% CdS/Al2O3(n) [50% wt of CdS supported on neutral alumina]
prepared in 10% NH3 solution
30N25 30% CdS/Al2O3(n) [30% wt of CdS supported on neutral alumina]
prepared in 25% NH3 solution
10A 10% CdS/Al2O3(a) [10% wt of CdS supported on acidic alumina]
prepared in 10% NH3 solution
30A 30% CdS/Al2O3(a) [30% wt of CdS supported on acidic alumina]
prepared in 10% NH3 solution
30B 30% CdS/Al2O3(b) [30% wt of CdS supported on basic alumina]
prepared in 10% NH3 solution
Silica Supported
10AE 10% CdS/SiO2 [10% wt of CdS supported on Aerosil silica]
prepared in 10% NH3 solution
30AE 30% CdS/SiO2 [30% wt of CdS supported on Aerosil silica]
prepared in 10% NH3 solution
50AE 50% CdS/SiO2 [50% wt of CdS supported on Aerosil silica]
prepared in 10% NH3 solution
30AE25 30% CdS/SiO2 [30% wt of CdS supported on Aerosil silica]
prepared in 25% NH3 solution
Contents I
CONTENTS
CHAPTER 1
1. Introduction 1
1.1. Semiconductor Photocatalysis 2
1.2. Pharmaceutical Importance and Thermal Synthesis of Homoallylamines 5
1.3. Synthesis of Homoallylamines through Semiconductor Photocatalysis 9
1.4. Pharmaceutical Importance of Organic Compounds Bearing Adamantane 13
1.5. Electronic Semiconductor-Support Interaction (SEMSI) 16
1.6. Aim of This Work 18
References 20
CHAPTER 2
2. Al2O3 Supported CdS 24
2.1. General Properties of Al2O3 as a Support Material 24
2.2. Synthesis of CdS/Al2O3 Photocatalysts 26
2.3. Characterization of Photocatalysts 28
2.3.1. Band-gap Energy Measurements by Diffuse Reflectance Spectroscopy 28
2.3.2. Determination of Quasi-Fermi Level of Electrons 34
2.3.2.1. Quasi-Fermi Level Determinations In The Presence of Hole Scavengers 40
2.3.2.2. Investigation of Light Intensity Effect on Quasi-Fermi Level Determinations 48
2.3.2.3. Energetic Position of Band Edges for CdS/Al2O3 Photocatalysts 50
2.3.3. IR Spectra of Al2O3 Supported CdS Powders 51
2.3.4. X-Ray Powder Diffractometry (XRD) 53
Contents II
2.3.5. High Resolution Transmission Electron Microscopy (TEM) 61
2.3.6. Interrogation of a Quantum-Size Effect 63
2.3.7. X-Ray Photoelectron Spectroscopy (XPS) 63
2.3.8. Time Resolved Photocharge (P-EMF) Measurements 68
2.4. Photocatalytic Activity Al2O3 Supported CdS 77
2.4.1. Determination of the Optimum Photocatalyst Amount 77
2.4.2. Photocatalytic Activity Measurements 79
2.5. Comparison of Al2O3 with SiO2 as Support Material for CdS 83
References 89
CHAPTER 3
3. CdS-Photocatalyzed Synthesis of Novel Homoallylamines 92
3.1. Photocatalytic Addition Reactions with N-Cinnamylideneaniline 92
3.1.1. Photocatalytic Addition Reactions of N-Cinnamylideneaniline with
cyclopentene, cyclohexene and α-pinene 92
3.1.1.1. HPLC Analysis 93
3.1.1.2. Mass Spectroscopy 96
3.1.1.3. IR 98
3.1.1.4. NMR 99
3.1.2. Thermodynamic Aspects 112
3.2. Photocatalytic Addition Reactions with N-(1-Adamantyl)-p-X-
benzaldehyde Imine (X: -H, -F, -Cl, -Br, -OCH3) 115
3.2.1. Photocatalytic addition reactions of N-(1-adamantyl)-p-chloro-
benzaldehyde imine with cyclopentene, cyclohexene and α-pinene 115
3.2.1.1. HPLC Analysis 116
3.2.1.2. Mass Spectroscopy 118
3.2.1.3. Structure Determinations by NMR and X-Ray 120
3.2.2. Photocatalytic Addition Reactions of N-(1-Adamantyl)-p-X-benzaldehyde
Imine (X: -H, -F, -Cl, -Br, -OCH3) with Cyclohexene 129
Contents III
3.2.3. Photocatalytic Addition Reactions of N-(1-Adamantyl)-p-X-benzaldehyde
Imine (X: -H, -F, -Cl, -Br, -OCH3) with α-Pinene 135
References 141
CHAPTER 4
4. Summary 142
CHAPTER 5
5. Zusammenfassung 148
CHAPTER 6
6. Experimental Section 155
6.1. General Methods 155
6.1.1. Irradiation Apparatus and Lamps 155
6.1.2. Solvents and substances 158
6.1.3. Spectroscopic and analytical methods 159
6.2. Quasi-Fermi Level Measurements 168
6.2.1. Influence of Hole Scavengers 169
6.2.2. Influence of Light Intensity 169
6.3. Synthesis of CdS Photocatalysts 170
6.3.1. Unsuppoted CdS (CdS-A) 170
6.3.2. SiO2 supported CdS 170
6.3.3. Al2O3 supported CdS 170
6.4. Photocatalytic Activity Measurements 172
6.5. Syntheses 173
6.5.1. Addition reactions with N-Cinnamylideneaniline 173
6.5.1.1. Synthesis of N-cinnamylideneaniline (6) 173
Contents IV
6.5.1.2. Synthesis of N-(1-(cyclopent-2-enyl)-3-phenylallyl)benzenamine (7a) 173
6.5.1.3. Synthesis of N-(1-(cyclohex-2-enyl)-3-phenylallyl)benzenamine (7b) 175
6.5.1.4. Synthesis of N-(1-(4,6,6-trimethylbicyclo[3.1.1]hept-3-en-2-yl)-3-
phenylallyl)benzenamine (7c) 176
6.5.2. Addition reactions with N-Adamantyl-p-X-benzaldehyde imine
(X: -H, -F, -Cl, -Br, -OCH3) 177
6.5.2.1. Synthesis of N-Adamantyl-p-X-benzaldehyde imine 177
6.5.2.2. Addition reactions with N-Adamantyl-p-chloro-benzaldehyde imine 178
6.5.2.2.1. Cyclopentene addition to N-Adamantyl-p-chloro-benzaldehyde imine 178
6.5.2.2.2. Cyclohexene addition to N-Adamantyl-p-chloro-benzaldehyde imine 181
6.5.2.2.3. α-Pinene addition to N-Adamantyl-p-chloro-benzaldehyde imine 182
6.5.2.3. Influence of p-Substituent 183
6.5.2.3.1. Addition reactions of cyclohexene to N-Adamantyl-p-X-benzaldehyde
Imine derivatives (X: -H, -F, -Cl, -Br, -OCH3) 183
6.5.2.3.1.1. Addition of cyclohexene to N-Adamantyl-benzaldehyde imine 183
6.5.2.3.1.2.Addition of cyclohexene to N-Adamantyl-p-fluoro-benzaldehyde imine 184
6.5.2.3.1.3. Addition of cyclohexene to N-Adamantyl-p-chloro-benzaldehyde imine 185
6.5.2.3.1.4. Addition of cyclohexene to N-Adamantyl-p-bromo-benzaldehyde imine 185
6.5.2.3.1.5. Addition of cyclohexene to N-Adamantyl-p-methoxy-benzaldehyde imine 186
6.5.2.3.2. Addition reactions of α-pinene to N-Adamantyl-p-X-benzaldehyde
Imine derivatives (X: -H, -F, -Cl, -Br, -OCH3) 188
6.5.2.3.2.1. Addition of α-pinene to N-Adamantyl-benzaldehyde imine 188
6.5.2.3.2.2.Addition of α-pinene to N-Adamantyl-p-fluoro-benzaldehyde imine 189
6.5.2.3.2.3.Addition of α-pinene to N-Adamantyl-p-chloro-benzaldehyde imine 190
6.5.2.3.2.4. Addition of α-pinene to N-Adamantyl-p-bromo-benzaldehyde imine 190
6.5.2.3.2.5. Addition of α-pinene to N-Adamantyl-p-methoxy-benzaldehyde imine 191
6.6. Crystal Structure Determinations 193
References 253
Chapter 1. Introduction 1
CHAPTER 1 1. Introduction
Due to everyday increasing environmental problems, R&D and management of
environmentally friendly chemical processes have become an obligation. According to this
global necessity many scientific and industrial R&D projects have been directed onto the
way of investigation and application of new, clean, efficient chemical technologies in last
decades. Designing of such new methods requires economically appropriate practice of
them as well. Therefore, the basic aim of research studies in this frame is to minimize by-
or waste products and maximize the main product in the most suitable and clean way.
In this respect, heterogeneous phase photocatalysis arises as a favorable process which
competes with the conventional methods. The scientific research activities dealing with
heterogeneous photocatalysis not only suggest environmentally friendly methods but also
induce the development of better and more efficient catalyst preparations upon a better
understanding of the mechanism of photocatalysis. However, due to the utilization of these
materials for maximum economic and environmental benefits, a better clarification must be
elucidated for the relationship between photocatalytic properties and surface chemistry.
From another point of view, using such photocatalysts in synthetic operations is also an
important and attractive branch of present research projects. All this may lead to a cleaner
alternative for known processes and to novel synthetic methods for the production of
otherwise not or more difficult obtainable compounds.
Chapter 1. Introduction 2
1.1. Semiconductor Photocatalysis
Semiconductors are particularly useful in photocatalysis because of their favorable
combination of electronic structure, light absorption properties, charge transport
characteristics, and excited-state lifetimes. [1] Their quite good stability under photolysis
conditions without significant degradation [2] is another attractive feature of them.
Semiconductor photocatalysis is initiated when a semiconductor is illuminated with
photons whose energy is equal or greater than the band-gap energy. [3, 4] In the proposed
mechanism of semiconductor photocatalysis, a photocatalytic reaction may proceed via
several steps [1, 5, 6] (Figure 1.1):
1. Adsorption of substrates onto the surface of the semiconductor
2. Excitation of the semiconductor by light of suitable energy and creation of electrons
in the conduction band and of holes in valence band (Eq. 1)
3. Charge trapping (Eq. 2) which must occur much faster than recombination (Eqs.
3,4)
4. Interfacial electron transfer from/to adsorbed substrates (rapid chemical reaction)
and formation of the final products
5. Desorption of the products
The photogenerated electron/hole pairs in a semiconductor can be thought of as strong
reducing and oxidizing surface centers. They can exchange electrons with donors and
acceptors, if their redox potentials lie within the band-gap. In such a case, thermodynamic
feasibility is fulfilled for the interfacial electron transfer. [7]
Chapter 1. Introduction 3
h+
e-
hν
e-tr
e-r
h+tr
h+r
CB
VB
AA
DD
ktr
ktr
ke
krc
ketr
krctr
ker
krcr
kox
kred
Figure 1.1: Photophysical and photochemical processes in semiconductor photocatalysis.
CdShv
CdS (h+/e-) Absorption (1)
CdS (h+/e-)ktr
CdS (htr+/etr
-)/(hr+/er
-)
CdS (h+/e-)ke
CdS + hν´
CdS (h+/e-)krc
CdS + ∆T
Charge Trappingat unreactive /reactive (2) surface sites
Radiative (3)
Non-radiative (4)
Recombination
Aad + er-
kredAad -
Dad + hr+
koxDad +
Reduction (5)
Oxidation (6)
IFET
Chapter 1. Introduction 4
The diffusion of conduction band electrons and valence band holes from the bulk to the
surface and their trapping occur very rapidly (Figure 1.1, ktr). Transit time for conduction
band electrons (Figure 1.1, kred) have been reported in the range of ps because of their low
effective mass and high mobility. [8] The photogenerated charge carriers can reach the
surface very quickly and become trapped before they recombine. [9] The latter process
usually occurs in µs range. Consequently, the interfacial electron transfer from/to adsorbed
substrates can successfully compete with recombination.
As a consequence of rising interest in semiconductor photocatalysis, publications increased
in recent years. Photo-Kolbe reactions [10, 11], conversion of primary amines to secondary
amines [12, 13], isomerizations [14-16], dimerizations [17, 18], substitutions [19, 20], condensations [21], alkylations [22, 23] and allylations [24] are some examples that can be encountered in the
literature. Research activities to perform organic synthesis through semiconductor
photocatalysis have been depicted [2, 7, 25, 26] over the last years. In only a few cases
semiconductor photocatalyzed organic synthesis of novel compounds has been successfully
achieved on a gram scale. [27-35]
Chapter 1. Introduction 5
1.2. Pharmaceutical Importance and Thermal Synthesis of
Homoallylamines
Nitrogen-containing organic molecules are present widely in nature since they are essential
to life by playing a vital role in the metabolism of all living cells [36] and also because of
their biologically active forms such as amino acids or alkaloids. [37] Thus, this crucial role
makes them the most important compounds in synthetic chemistry. [37]
For the synthesis of e.g. amino acids, allylamines are considered as ideal building blocks,
and these compounds are also used as starting materials in important industrial processes. [37] It has been reported that more than 75% of drugs and drug candidates incorporate amine
functionality. [38] Therefore, development of new methods for the synthesis of amines can
be thought as a major objective for synthetic chemists.
The incidence of fungal infections has dramatically increased during the last years. [39]
Fungal infections have debilitating effects on human metabolism and they affect the skin,
keratinous tissues and mucous membranes. [40] Eradication of systemic mycoses and some
forms of dermatomycoses are very difficult and they are the cause of a great mortality in
patients receiving antineoplasic chemotherapy, organ transplants or suffering from
AIDS. [39] Because of the toxicity [40] of many currently available drugs, it has become
necessary to find out alternative more potent and safer antifungal agents. [40]
Allylamines have been recently used to treat superficial mycoses [40] and the anti-fungal
activity of a series of homoallylamines have been determined [39-41] by pointing out the
importance of such structures (Figure 1.2) as alternatives against fungal infections which
are considered as building blocks [42] for drug design.
NH
R
R'
Figure 1.2: General structure of antifungal homoallylamines. [40]
Chapter 1. Introduction 6
However, any mutual catalytic method for drug design must fulfill some conditions to be
considered as an efficient route [43]:
1. Substrate purity and its effect on catalyst activity
2. Substrate-to-catalyst ratio and turnover number
3. Ease of isolation of the final product
4. Optical purity of the final product
5. Isolation and recycling of the catalyst
6. Economic viability of the process in comparison with any alternative synthetic
routes.
Although conventional catalytic techniques are of basic importance in producing fine
chemicals and pharmaceuticals, [44] they may cause environmental pollution because of
formation of by-products. Therefore, for an environmentally friendly production method a
further point must be considered. It is the E-factor which is a term defining the quantity of
by-products formed per kg of product. [45] A view of Table 1.1 demonstrates the necessity
and importance of developing new environmentally friendly, efficient production methods
in drug design because of quite high level of E-factor for pharmaceuticals in comparison
with the other industrial sectors. Such a high level of E-factor arises from multi-step
syntheses using stoichiometric reagents that result in accumulation of inorganic salts as by-
products.
Significant efforts are made on development of homogeneous catalytic techniques because
they can be molecularly tuned through ligand and metal modification. Although molecular
tuning of heterogeneous catalysts is more difficult, they have enormous advantages
compared to their homogeneous counterparts in terms of ease of handling, separation,
catalyst recovery, and regeneration that make them industrially attractive. [44]
Industry Sector Amount of Product
E-factor (kg by-product/kg product)
Bulk chemicals 104-106 < 1-5 Fine chemicals 102-104 5-50 Pharmaceuticals 10-103 25-100
Table 1.1: E-factors for various sectors of the chemical industry. [44]
Chapter 1. Introduction 7
Recently, many projects tried to develop new synthesis methods in order to obtain
homoallylamines because of their pharmaceutical value. In some work biological or anti-
fungal activity of homoallylamines has been also dealt with. Diastereoselective or
enantioselective synthesis methods are further in the centre of modern research because in
many cases biological action is determined by the optical purity. The synthesis and also
fungistatic effects of homoallylamines acting against dermatophytes has been reported by
Vargas et al.. [40] A series of aldimines had been converted into the N-substituted
unsaturated amines by nucleophilic addition of allylmagnesium bromide to the C=N bond
of these imines. After purification by column chromatography, corresponding isolated
homoallylamine products had been obtained in yields of 12–94%. In another work, various
homoallylamines from aldimines had been prepared in order to evaluate their antifungal
properties against human pathogenic fungi and study the structural requirements for the
antifungal activity. [39] The 4-aryl- or 4-alkyl-4-N-aryl-amino-1-butenes have been obtained
by addition of allylmagnesium bromide to aromatic aldimines. After purification by
column chromatography, products were isolated in yields of 43-98%.
Gallium metal mediated allylation (through sonication) of imines has been presented as
another alternative synthesis method under solvent-free conditions in order to get
homoallylic secondary amines. The isolated yields were in the range of 5-94% except for
N-cinnamylideneanil (0%). [42] The synthesis of optically active homoallylamines, which
are interesting intermediates in the synthesis of biologically active natural products, had
been accomplished by enantioselective allylboration of N-aluminum imines with chirally
modified allylboron reagents in yields of 11-70%. [46] A three-component reaction by using
crotylsilane for the synthesis of homoallylamines from aldehydes showing syn-
diastereoselectivity in the synthesis [47] and also diastereoselective allylation of imines
derived from (R)-phenylglycine amide via allylzinc bromide [48] have been reported. In
addition, the first efficient asymmetric synthesis of an α-trifluoromethylated
homoallylamine based on the (S)-1-amino-2-methoxymethylpyrrolidine (SAMP)- or (R)-1-
amino-2-methoxymethylpyrrolidine (RAMP)-hydrazone method has been published by
Funabiki et al.. [49, 50]
Some methods for synthesis of homoallylamines are summarized in Figure 1.3.
Chapter 1. Introduction 8
N
R2 R3
R1
HN
R2
R1
R3
SiMe3
SnBu3
Br
Br
Br
/ TBAF / THF / 4 A MS / reflux
(a), (b) 30-92 %
I. MeSiCl / CH3CN II. NH4F
(c) 63-96 %
I. Mg or Zn / THF / 0.5-2 h II. NaHCO3 (aq)
/ Mg / Et2O / 10 °C
(d) 82-99%
(e) 53-98 %
I. Ga / 12h sonication II. H2O
(f) 0-94 % (0% for N-cinnamylideneanil)
N
R H
Al(i-Bu)2I. Triallylborane / THF / 5h / RT
II. H3O+
III. NH4OH 11-70%
NH2
R
N
R H
CONH2
PhBrZn
THF, 0°C to RT
3 steps
78-84%
NH2
R
N
R2
H
R3
Cp2Zr
R1
CH3
R5R4 H+
R4
R5 HN
R3
R2
R1
Cp: Cyclopentadiene
R H
O
+ R'-NH2 + SiMe3
Lewis acid
syn anti
R
HNR'
+R
HNR'
R: CO2R'; SO2R2
60-96%
16-96%
(g)
(h)
(i)
(j) Figure 1.3: Some literature methods (a)[51], (b)[52], (c)[53], (d)[36], (e)[39], (f)[42], (g)[46], (h)[48],
(i)[37], (j)[47] for homoallylamine synthesis. (R1, R2: Aryl, Alkyl, R3: Aryl, Alkyl or -H)
Chapter 1. Introduction 9
1.3. Synthesis of Homoallylamines through Semiconductor
Photocatalysis
In the years of 1996-1997 Kisch et al. presented a different photochemical alternative to all
these conventional synthesis methods of homoallylamines. [30, 32]
According to this method, novel homoallylamines had been synthesized through addition
of cyclopentene to aldimines in 40-80% of yield (Figure 1.4). [30] The hydrodimer of the
imine, that is the dimer of a postulated α-aminobenzyl radical, has been also observed as
by-product.
N
H
Ar2
Ar1MeOH
NAr2
Ar1
HH
Ar2CH-NHAr1
Ar2CH-NHAr1+hν, CdS
1a - d 2a - d 3a - d
+
1a 1b 1c 1dAr1 4-ClC6H4 2,6-Cl2C6H3 4-ClC6H4 4-MeOC6H4
Ar2 4-ClC6H4 C6H5 3,5-Me2C6H3 4-MeC6H4
Figure 1.4: CdS-photocatalyzed linear addition of cyclopentene to Schiff-Bases. [30]
When the aldimine is replaced by a trisubstituted imine like N-phenylbenzophenone imine,
new homoallylamines have been synthesized in yields of 30-75% (Figure 1.5). [32]
Chapter 1. Introduction 10
NPh
Ph Ph
R H MeOH NPh
Ph Ph
HR+
hν, CdS
4 a - g 5a - g
R :OO
Me
Me
a b c d
Me MeO
O
e e' f f' g
Figure 1.5: The synthesis of homoallyl amines by CdS-catalyzed linear photoaddition of
olefins and enol/allyl ethers to N-phenylbenzophenone imine. [32]
The CdS-photocatalyzed addition of olefins to imines affords homoallylamines in a one-
step reaction without any detrimental by-product (in the case of ketimine). Working with a
heterogeneous phase catalyst facilitates the work-up process because the catalyst can be
easily removed from the product solution by filtration. This method can be also considered
as economic and environmentally friendly because it is possible to carry out this reaction
with visible light which allows solar production opportunities.
From another point of view, CdS-photocatalyzed addition reactions were the first
achievement of semiconductor-photocatalyzed organic synthesis of novel compounds on a
preparative scale. Mechanistic investigations led to the following.
It was shown that olefin and imine adsorption onto the photocatalyst surface occurs via
hydrogen bonding and Br∅nsted acid sites, respectively. [29, 54, 55] According to the proposed
mechanism, photogenerated charges are transferred to the adsorbed substrate (IFET) which
competes successfully with the charge-recombination as it has been mentioned in Section
1.1. At this step, the conduction band electron and a proton are transferred to the imine and
the hole in the valence band oxidizes the olefinic substrate under concomitant
deprotonation. Thus, an α-amino radical and an ally radical are formed on the surface of
the photocatalyst simultaneously.
Chapter 1. Introduction 11
C
N
RAr
Ar
Cd
Cd
Cd
Cd
Cd
Cd
CdCd
S
SS
S
S
S
S
S
S
Cd
Cd
Cd
Cd
Cd
Cd
CdCd
S
SS
S
S
S
S
S
S
hν
h r e r
H
C
HN
R
Ar
Ar
C NH
C N
H
ArArH
ArAr
H
O
O
O
O O
O
O
OH
H
H
H
H
H
H
H
H
H
H
H
HH HH HH HH
H
H
H
H
H
H
H
H
H
H
H
H
HH
HH
HH
HH
HH
HH
HH
HH
HH
C NH
Ar
Ar
R ADHD
R= H
+ H
+ e
C NAr
HR
Ar
HRED
Figure 1.6: Mechanistic proposal for CdS-photocatalyzed C-C coupling reactions between
Schiff bases and olefins (e.g. cyclopentene). [30]
These two intermediates may couple regioselectively to give a C-C heterocoupling product
(AD) as the main product (Figure 1.6). [30, 32] In no cases a C-N heterocoupling product has
been observed. Thus, differently from thermal routes, which usually involve usage of
organometallic intermediates, the reaction is much easier to perform and regioselective to C
atom of C=N double bond. Heterocoupling of the intermediates takes place at the solid-
solution interface as it has been clarified by pressure-dependent experiments. [29, 55] In some
cases (R= H, Figure 1.6), the α-amino radical may also dimerize to give a hydrodimer
(HD). [30] Formation of the reduction product (RED) can be observed depending on the
light intensity since it is a 2e-/2h+ process (Figure 1.6). [31]
According to thermodynamics, the feasibility of the IFET depends on the redox potentials
of adsorbed substrates and band edge positions. Whenever the reduction potential of the
acceptor substrate is below the conduction band edge and the oxidation potential of the
Chapter 1. Introduction 12
donor substrate above the valence band edge, interfacial electron transfer between the
reactive e–-h+ pair and substrates is thermodynamically feasible. [26]
The energetic positions of the band edges can be influenced by catalyst preparation
(various preparation methods, surface impurities, using of a support or metal, etc.), pH,
type of solvent and substrate adsorption. [26] In this aspect another important point that must
be noted is the conditions at which the band edges of a semiconductor are given. Since the
band edge locations direct the driving force for the interfacial electron transfer [26], any shift
that may occur in their position will influence the electron transfer rate. Therefore, the
reaction conditions in which the reaction will be carried out such as pH value, type of
solvent may play important role because of their influence on band edge positions of
photocatalyst.
Particle size and specific surface area of a semiconductor photocatalyst have been also
pointed out as important properties that may have influence on photocatalysis by affecting
the charge-recombination rate, which is connected to IFET rate, and determining the
chemoselectivity, respectively. [26]
Chapter 1. Introduction 13
1.4. Pharmaceutical Importance of Organic Compounds Bearing
Adamantane
Influenza A is described as a major respiratory tract disease affecting millions of people
each year (approximately 20,000 deaths per year in the United States [56]). It is
characterized by the abrupt onset of constitutional and respiratory signs and symptoms
(e.g., fever, myalgia, headache, severe malaise, nonproductive cough, sore throat and
rhinitis). [57] Amantadine and rimantadine (Figure 1.7) are known as anti-influenza A drugs
that inhibit virus replication at micromolar concentrations. [58-61]
NH2NH2H3C
[1] [2]
Figure 1.7: Structure of amantadine [1] and rimantadine [2].
1-adamantaneamine⋅HCl (amantadine⋅HCl) has been studied in the years of 60’s and its
activity towards influenza A was reported. [62-65] A systematic study of the effect of
structural variations of 1-adamantanamine upon inhibition of influenza A was published in
1970 by Aldrich et al.. [66] In addition, synthesis and activity against influenza A virus of 3-
(2-adamantyl)pyrrolidines (Figure 1.8) were shown. [67]
Chapter 1. Introduction 14
N R
R: H, CH3, C2H5, n-C3H7, n-C4H9, CH2CH2NMe2 CH2CH2NEt2, H2CH2CN
Figure 1.8: Structure of 3-(2-adamantyl)pyrrolidines that show antiinfluenza A virus
activity. [67]
Some adamantane derivatives possessing considerable antibacterial activity were found in
the 80’s and 90’s. [68-70] For example 4-(adamant-1-ylmethoxycarbonyl)-N-(5-
carboxypentamethylene) phthalimide or 4-(adamant-1-ylmethoxycarbonyl)-N-(L-alanyl)
phthalimide were tested against Staphylococcus aureus, Bacillus sp., Micrococcus flavus
and Enterococcus faecium. [71]
Parkinson's disease is a disorder of certain nerve cells in a part of the brain (substantia
nigra) that produces dopamine. The brain uses dopamine (chemical messenger, or
neurotransmitter) to direct and control movement. In Parkinson's disease, these dopamine-
producing nerve cells break down, dopamine levels drop, and brain signals directing
movement become abnormal. Amantadine and its modified analogues rimantidine,
tromantidine and memantine received attention as promising drugs also for the treatment of
Parkinson’s disease. [72, 73]
Alzeihmer’s disease (AD) is defined as a neurodegenerative disorder which is
pathologically characterized by the progressive deposit in the brain of a specific form of
amyloid, amyloid-β peptides (Aβ) [74] and memantine (3,5-dimethyl-1-adamantanamine
hydrochloride) were considered as promising compounds also in the way of treatment of
this disease. [75]
Some types of amantadine derivatives were reported by Kolocouris and coworkers [76] to
display little activity against HIV (Human Immunodeficiency Virus, the causative agent of
AIDS [77]) strains.
Chapter 1. Introduction 15
Tumor necrosis factor-α (TNF-α) is a cytokine produced mainly by activated
monocyte/macrophages [78, 79] and considered as an attractive target molecule for the
development of biological response modifiers (BRMs). [80] N-(1-adamantyl)phthalimide to
enhance TNF-α production in the 12-O-tetradecanoylphorbol-13-acetate-stimulated human
leukaemia HL-60 cell line [81] and certain novel adamantane heterocyclic derivatives
(adamantylaminopyrimidines and -pyridines) that enhance TNF-α production in murine
melanoma cells transduced with the human TNF-α gene [82] were reported. Of the studied
series of adamantylated heterocycles, 2-adamantylamino-6-methylpyridine and
2-adamantylamino-4-methylpyrimidine were indicated as the most biologically active
compounds to enhance the induction of TNF-α in genetically modified murine melanoma
cells transduced with the gene for human TNF-α. [80]
Recently synthetic investigations, biological activity and practical applications of
heteryladamantanes (adamantyl-substituted heterocycles) were reviewed by Litvinov. [83] In
this review, a wide range of possible practical applications of adamantane and its
derivatives have been mentioned concerning hypoglycemic, antitumor, immunodepressant,
antibacterial and fungistatic, hormonal, analgesic and antipyretic, anti-inflammatory,
cholagogic, antiarhythmic, sedative, antimalarial, and anticholesterase activity, stimulation
of the central nervous system stimulant.
Chapter 1. Introduction 16
1.5. Electronic Semiconductor-Support Interaction (SEMSI)
It is known that supporting CdS [84] or TiO2 [85] on silica significantly shifts band edges and
band-gap energy values of the semiconductor. In addition to that, it influences the
photocatalytic properties of the semiconductor [84], and all these changes are generally
ascribed to a modification of the electronic properties of the semiconductor particles
resulting from a semiconductor-support interaction. [84, 85] This interaction is due to the
formation of covalent bonds Cd-O-Si or Ti-O-Si since simple grinding of the two
components does not afford the same result. Accordingly, the preparation method for
CdS/SiO2 consists of stirring a suspension of silica in aqueous CdSO4 solution followed by
filtration and subsequent drying at RT.
For silica supported CdS, a band-gap widening was observed which increases with
decreasing coverage. It has been found that the quasi-Fermi levels are shifted to more
negative values (see Figure 1.9 (a)). Furthermore, the lifetime of charge carriers is
increased by the factor of 5. [84] Therefore, it is not unexpected that the rate of the addition
reaction is increased at least 10 times when CdS is supported onto silica (see Figure 1.9
(b)). Based on these experimental results, it has been concluded that all observed changes
originate from the influence of electronic semiconductor-support interactions (SEMSI)
which is a consequence of the presence of Cd-O-Si bonds. [84, 86]
In the case of silica supported TiO2 an anodic shift of the quasi-Fermi levels and a band-
gap widening are observed. [85] The shift in band edges was identified not only by
photovoltage measurements but also by XPS analysis, and formation of Ti-O-Si linkages
was confirmed by diffuse reflectance infrared Fourier transform spectroscopy. Contrary to
CdS/SiO2, in this case the lifetime of charge carriers is decreased and the photocatalytic
activity becomes therefore much lower. [85]
It is noted that any observed shift in band edge positions and band-gap energy can not arise
from a quantum-size effect since the crystallite size is not smaller than 5-6 nm and does not
differ significantly for various coverages.
Chapter 1. Introduction 17
2,5
2,0
1,5
1,0
0,5
0,0
-0,5
CdS-A 50%
Ebg [+0.01 eV]E
(FB)
[V]
VB [+0.02 V]
CB [+0.01 V]
photocatalysts
2.58 2.53 2.49 2.40
1.99 2.12 2.11
2.02
-0.59-0.41-0.38-0.38
12%30%
(a)
(b)
E [V
]
Figure 1.9: Consequences of electronic semiconductor-support interaction for silica
supported CdS. [84, 86]
(a) Variation of band edge positions (+ 0.02 V) with coverage; pH= 7.
CdS-A: unsupported CdS, 12%: 12%CdS/SiO2, 30%: 30%CdS/SiO2, 50%: 50%CdS/SiO2,
(b) Variation of the rate of photocatalytic activity with decreasing coverage (in an addition
reaction between cyclopentene and N-(4-chlorobenzylidene)-4-chloraniline).
A: unsupported CdS, B: 50%CdS/SiO2, C: 30%CdS/SiO2, D: 12%CdS/SiO2.
Chapter 1. Introduction 18
1.6. Aim of This Work
Electronic semiconductor-support interaction (SEMSI) is a recently found effect for silica
supported semiconductors which can be considered particularly important since in the case
of CdS it improves the performance of the photocatalyst. This effect leads to a widening of
the band-gap, longer lifetime of light-generated charges, and acceleration of the
photocatalytic reaction.
In view of the fact that silica induced opposite effects on titania, as depicted in the previous
section, it was of interest to find out what will happen when CdS would be supported onto
another oxide like alumina.
Therefore, in the first part of this work CdS powders were supported with alumina, which
is another well known and widely used catalyst support, and the SEMSI effect was
investigated. Characterization studies of these photocatalysts were done to determine their
optical, photoelectrochemical and surface properties. In addition, their photocatalytic
activities were compared through a CdS-photocatalyzed addition reaction between a Schiff
base and cyclopentene.
The second part constitutes semiconductor photocatalyzed organic syntheses. As
mentioned in Section 1.3 the linear addition of cyclic olefins to imines opens a new route
to novel homoallylamines on a gram scale and is much easier than conventional methods to
perform. With particular attention, these reactions proceed chemoselectively through a
radical C-C coupling step.
In first set of synthesis work, in order to investigate the general applicability of the
photocatalytic addition reactions between imines and olefins, such type of synthesis work
was extended to an α,γ-unsaturated imine like N-Cinnamylideneaniline. The investigation
was focused on two aspects. Firstly, finding out whether the addition of the intermediate
allylic carbon radical takes place regioselectively either in the α-position or γ-position to
the imine function. And secondly, to synthesize novel homoallylamine derivatives on a
gram scale.
Chapter 1. Introduction 19
Many adamantane derivatives are interesting compounds because of their diverse
biological activity as mentioned briefly in Section 1.4 and the development of new
synthesis methods leading to such derivatives, receives great attention in synthetic and
pharmaceutical chemistry.
In the second set of synthesis work, homoallylamine synthesis studies were conducted by
using adamantane ring containing imine substances. A series of novel homoallylamine
derivatives bearing an adamantyl-ring were synthesized through CdS photocatalyzed C-C
coupling reactions between cyclic olefins (cyclopentene, cyclohexene and α-pinene) and
various N-(1-adamantyl)-benzaldehyde imines.
Chapter 1. Introduction 20
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Chapter 2. Al2O3 supported CdS
24
CHAPTER 2 2. Al2O3 Supported CdS
2.1. General Properties of Al2O3 as a Support Material
It has been reported that supported semiconductors, in thermal catalysis exhibit better
activity than unsupported ones [1] because the support induces a high dispersion of active
ingredients. [2-5] Basic parameters for the selection of a support material are specific surface
area, which is related with the adsorption capacity of the material, the nature of the surface
groups, their acid-base properties, their hydrophilic-hydrophobic balance, and the surface
charge of the support in water. [6] Any minor experimental differences occurring during
catalyst preparation may be of crucial consequence.
In photocatalysis the active ingredients on a supported photocatalyst should be deposited
only on or near the external surface of the support because light cannot penetrate deep
inside a support material. [2]
Alumina, which is a highly insulating metal-oxide [7] is similar in use to silica and available
in acidic, neutral, and basic form. Acidic and neutral grades are typically made by washing
basic alumina with HCl until the desired pH of aqueous slurry is reached. Because of their
thermal and chemical stability aluminum oxides have been widely used as catalyst
support. [8, 9]
In an Al2O3/water system, the OH groups on the solid surface are the most important sites
for surface interactions. These groups can act as acids or bases depending on the pH of the
solution. With decreasing pH, the net positive surface charge increases and with increasing
Chapter 2. Al2O3 supported CdS
25
pH, the charge decreases and becomes negative. It is also known that the adsorption
capacity for acidic alumina is only weakly pH dependent; whereas it is much stronger for
basic alumina. [10]
Some properties of alumina used in this work are given in Table 2.1. (For other
specifications, see Experimental Section 6.1.2) Measured pH values (for 100 g/l)
correspond to their aqueous suspensions at RT.
OH group densities were determined by thermogravimetry, specific surface areas by the
BET method (for details, see Experimental Section 6.1.3.9).
Si
O
H
Si Si
O
Si
O
Al
O
H
Al Al
OOHH
(a) (b) (c)
(d) (e) (f) Figure 2.1: Characteristic surface groups on silica and alumina (a) hydrophilic Si-OH
groups, (b) hydrophobic Si-O-Si, (c) basic Si-O- groups, (d) neutral Al-OH, (e) acidic Al-
OH2+, (f) basic Al-O- groups. [11]
Chapter 2. Al2O3 supported CdS
26
Support Material pH of aqueous
suspensions OH/nm2
Specific Surface Area
[m2g-1]
Al2O3 Aldrich, neutral 6.8 3.8 189
Al2O3 Aldrich, acidic 5.0 6.2 150
Al2O3 Aldrich, basic 10.0 4.3 146
Table 2.1: Specific surface areas, OH group densities, and pH values (for 100 g/l of
concentration) of used neutral, acidic and basic Al2O3 employed in this work.
2.2. Synthesis of CdS/Al2O3 Photocatalysts
Alumina-supported photocatalysts containing 50, 30, and 10 wt% of CdS were prepared by
impregnating Al2O3 (neutral, acidic or basic type) with cadmium sulfate and precipitation
with sodium sulfide in ammonia solution (10% or 25% NH3(aq)). Aluminum oxide was
stirred in aqueous NH3 (10% or 25%) prior to CdSO4 addition. After stirring overnight
Na2S was dissolved in water and added drop wise into the CdSO4/Al2O3 mixture within a
period of 1,5 h. The resulting yellow suspension was stirred for 20 h. After separation by
filtration, the residue was washed with water to constant pH (pH=7), dried over P2O5 in a
vacuum desiccator, and ground in an agate mortar. All powders were prepared, dried, and
stored under nitrogen. Unsupported CdS was prepared according to the same method but
without using a support material.
H2O
HO-[M]
Cd
OH2
H2O
OH2
-O-[M]
OH2OH2
H2O
H3O+
CdO [M]
+
2+
+
- H2O
+
OH2
OH2
OH2H2O
H2O
Figure 2.2: Formation of Cd-O-[M] bonds
Chapter 2. Al2O3 supported CdS
27
As can be seen in Figure 2.2, if the preparation is performed in more basic impregnation
solution, due to the increased concentration of surface [M]-O- ions the equilibrium should
be shifted to the right side and therefore the concentration of Cd-O-M bonds should be
increased.
Listed actual %CdS values in Table 2.2 represent CdS amounts in percentages calculated
from %S which was obtained by elemental analysis. According to actual %CdS values, all
10 wt% supported CdS samples contain about 8-9%, all 30 wt% supported samples about
21-23%, and all 50 wt% supported samples 31-34% of CdS independently from the
preparation method and support properties.
Results of Elemental Analysis Photocatalysts
%S %H %N %C Actual %CdS
10NI 1.760 - 0.028 0.652 7.9
30NI 4.960 - 0.047 0.862 22.3
50NI 7.263 - 0.117 1.097 32.7
10NII 1.731 - - 0.112 7.8
30NII 4.820 - - 0.110 21.7
50NII 7.470 - - - 33.7
10NIII 1.822 - - 0.102 8.2
30NIII 5.082 - 0.015 0.210 22.9
50NIII 6.950 - 0.032 0.152 31.2
30N25 4.894 0.280 0.170 0.130 22.0
30B 4.890 - 0.115 0.074 22.0
10A 1.910 0.510 0.080 0.110 8.6
30A 4.709 - 0.179 0.115 21.0
Table 2.2: Results of elemental analysis for unsupported CdS and Al2O3 supported CdS
powders.
Chapter 2. Al2O3 supported CdS
28
Each preparation step during the photocatalyst preparation plays a very significant role. It
was reported that even the rapid mixing of Cd2+ and S2- solutions may lead to small
particles with a very narrow size distribution. [12]
It is also noted that storage of prepared powders under inert atmosphere is particularly
important otherwise slow oxidation causes formation of CdO at room temperature followed
by adsorption of water to give Cd(OH)2. [13]
2.3. Characterization of Photocatalysts
2.3.1. Band-gap Energy Measurements by Diffuse Reflectance Spectroscopy
Diffuse reflectance spectroscopy is a spectroscopic technique designed for opaque
samples [14] to determine their absorption characteristics. The data analysis can be
performed according to Kubelka-Munk theory.
Kubelka-Munk equation: F(R∞) = (1 - R∞) / 2 (R∞)2 = k / s (2.3.1.1)
k: absorption coefficient, s: scattering coefficient
R: the diffuse reflectance
(I0: the intensity of analyzing light, IR: the diffusely reflected light; R∞ = IR / I0)
Absorption of a photon by a semiconductor promotes electrons from the valence band to
the conduction band. The different electronic states within each band are characterized not
only by their energy, but also their momentum. [15] According to the selection rules for
photon absorption only transitions with zero net momentum change are allowed. [16]
Therefore, the magnitude and energy of the absorption process depend on the band
structure of the semiconductor. In the case of the excitation of an electron from the valence
band to the conduction band, if there is no change in momentum, the absorption probability
is high for this orbitally allowed transition and the semiconductor is called as a "direct band
gap" material, otherwise an "indirect band gap" material. [16]
Chapter 2. Al2O3 supported CdS
29
For a direct semiconductor the square of absorption coefficient is proportional to the energy
difference between the band-gap and incoming light [17] (Eq. 2.3.1.2).
[F(R∞)hν]2 ∝ (hν - Ebg) (2.3.1.2)
From the diffuse reflectance spectra, Kubelka-Munk function is obtained. From this value
the modified function [F(R∞)hν]2 was plotted versus energy (eV) assuming that all CdS
samples are direct [16] semiconductors. The intersection of the extrapolated value of
[F(R∞)hν]2 with the energy axis affords the band-gap energy.
1,6 1,8 2,0 2,2 2,4 2,6 2,8 3,00
10
20
30
40
50dcba
[F(R
∞)h
ν]2
hν / eV
Figure 2.3: Transformed diffuse reflectance spectra of unsupported and Al2O3(n)
supported CdS powders prepared according to the first method (see text).
(a) Unsupported CdS [CdS-A] (Ebg: 2.39 + 0.01 eV), (b) 50% CdS/Al2O3(n) [50NI]
(Ebg: 2.37 + 0.01 eV), (c) 30% CdS/Al2O3(n) [30NI] (Ebg: 2.39 + 0.01 eV), (d) 10%
CdS/Al2O3(n) [10NI] (Ebg: 2.43 + 0.01 eV).
Chapter 2. Al2O3 supported CdS
30
Al2O3(n) supported CdS powders were prepared by two different methods; Method A and
Method B. According to Method A, CdSO4 and Al2O3(n) were stirred together in 10%
NH3(aq) overnight before Na2S addition. Powders obtained by this method are named by
giving the amount of wt% of CdS, the acidity of the support material, suffix “I”.
Different from this, in a second method Al2O3(n) was stirred alone in 10% NH3 (aq) and
CdSO4 was added after 8h to the suspension and subsequently stirred overnight before
Na2S was added. Powders obtained by the second method are named by giving the amount
of wt% of CdS, the acidity of the support material, suffix “II”. Figures 2.3 and 2.4 contain
the corresponding plots from which the band-gap energy has been calculated.
1,6 1,8 2,0 2,2 2,4 2,6 2,8 3,00
25
50
75
100
d
ecb
[F(R
∞)h
ν]2
hν / eV
a
Figure 2.4: Transformed diffuse reflectance spectra of unsupported and Al2O3(n)
supported CdS powders prepared according to the second method (see text).
(a) Unsupported CdS [CdS-A] (Ebg: 2.39 + 0.01 eV), (b) 50% CdS/Al2O3(n) [50NII] (Ebg:
2.42 + 0.01 eV), (c) 30% CdS/Al2O3(n) [30NII] (Ebg: 2.43 + 0.01 eV), (d) 10%
CdS/Al2O3(n) [10NII] (Ebg: 2.45 + 0.01 eV), (e) 30% CdS/Al2O3(n) prepared in 25% NH3
[30NII25] (Ebg: 2.48 + 0.01 eV).
Chapter 2. Al2O3 supported CdS
31
Since a very small band-gap widening was observed (see Table 2.3) with the powders
obtained according to the second method, thereafter all powders were prepared according
to this procedure. 10%, 30% and 50% Al2O3(n) supported CdS powders were prepared
again (suffix “III”) according to the second method to check the reproducibility of the
obtained data. No significant differences were detected (see Table 2.3). 30% CdS/Al2O3
powder (30N25) was prepared by the second method also in more basic solution by using
25% NH3 (aq) instead of 10% to find out a mutual effect of pH. In addition to that, Al2O3(a)
and Al2O3(b) supported CdS powders were prepared to investigate the influence of acidity
and basicity of Al2O3 on the characteristics of supported CdS (Figures 2.5 and 2.6).
1,8 2,0 2,2 2,4 2,6 2,8 3,00
25
50
75
100
125 gfec
[F(R
∞)h
ν]2
hν / eV
a
Figure 2.5: Transformed diffuse reflectance spectra of Al2O3(a) supported CdS powders
and comparison of their band-gap energies with CdS-A, 30NII and 30NII25.
(a) Unsupported CdS [CdS-A] (Ebg: 2.39 + 0.01 eV), (c) 30% CdS/Al2O3(n) [30NII] (Ebg:
2.43 + 0.01 eV), (e) 30% CdS/Al2O3(n) prepared in 25% NH3 [30NII25] (Ebg: 2.48 + 0.01
eV), (f) 30% CdS/Al2O3(a) [30AII] (Ebg: 2.43 + 0.01 eV), (g) 10% CdS/Al2O3(a) [10AII]
(Ebg: 2.46 + 0.01 eV).
Chapter 2. Al2O3 supported CdS
32
In the case of basic alumina supported CdS (30BII) no difference in band-gap energy value
was observed as compared to the unsupported CdS. However, about 40 and 70 meV of
band-gap widening was observed for 30% and 10% acidic alumina supported materials,
respectively.
The results of band-gap energy measurements were presented together in Table 2.3. These
results reveal that the largest band-gap widening (90 meV) belongs to 30NII25 which was
prepared in a more basic impregnation solution. In addition, as mentioned above,
supporting of CdS with the acidic alumina also leads to a slight band-gap widening.
1,8 2,0 2,2 2,4 2,6 2,80
25
50
75
100
cha
[F(R
∞)h
ν]2
hν / eV
Figure 2.6: Transformed diffuse reflectance spectra of Al2O3(b) supported CdS powder
and comparison of its band-gap energy with CdS-A, 30NII.
(a) Unsupported CdS [CdS-A] (Ebg: 2.39 + 0.01 eV), (c) 30% CdS/Al2O3(n) [30NII] (Ebg:
2.43 + 0.01 eV), (h) 30% CdS/Al2O3(b) [30BII] (Ebg: 2.41 + 0.01 eV).
Chapter 2. Al2O3 supported CdS
33
Photocatalyst Ebg
[+ 0.01 eV]
(e)
10NI 2.43
30NI 2.39 (a)
50NI 2.37
10NII 2.45
30NII 2.43 (b)
50NII 2.42
(e) (f)
10NIII 2.46 2.45
30NIII 2.43 2.43 (c)
50NIII 2.41 2.42
(d) 30NII25 2.48 2.49
30BII 2.41 2.38
10AII 2.46 2.46
30AII 2.43 2.44
Table 2.3: Band-gap energies of alumina supported CdS powders. (a) Prepared according
to the first method in 10% NH3(aq) (b) First set of preparations according to the second
method in 10% NH3(aq) (c) Repetition of (b) (d) Prepared according to the second method
in 25% NH3(aq) (e) Measured relative to BaSO4 as standard (f) Measured relative to Al2O3
standard (Al2O3(n) for Al2O3(n) supported powders, Al2O3(b) for Al2O3(b) supported
powder, Al2O3(a) for Al2O3(a) supported powders).
Chapter 2. Al2O3 supported CdS
34
2.3.2. Determination of Quasi-Fermi Level of Electrons
When semiconductor particles are dispersed in an electrolyte, interfacial transfer of mobile
charge carriers between semiconductor and electrolyte generates a “space charge layer”.
The space charge layer is the consequence of formation of a semiconductor-electrolyte
junction. [18] The electric field in this layer promotes the separation of electron-hole pairs
and the direction of the field is usually such that the minority carriers move to the surface. [19] Therefore, for an n-type semiconductor holes will move to the surface while electrons
move to the bulk constituting the charge separation.
Within the space charge layer band edges are bent (upward in the case of an n-type
semiconductor). In the absence of the space charge layer band edges are flat and the
potential of the Fermi level at this situation is called flat-band potential. [20]
If the size of the particles is smaller than the space charge layer width, band bending
becomes negligible [21] (see Figure 2.7). The thickness of the space charge layer depends
primarily on the dopant concentration and in general falls in the range of 100-1000 nm. [21]
Since the CdS powders prepared in our work have particle size around 8-20 nm, the
nonexistence of a space charge layer becomes clear.
For an n-type semiconductor, since the majority charge carriers are electrons, the Fermi
level lies close to the conduction band. Under illumination the Fermi-level splits into two
“quasi-Fermi levels”; nEF* for the electrons and pEF
* for the holes [17, 22] because of
nonequilibrium population in e- and h+ [22] (Figure 2.8). For highly doped semiconductors
the position of the Fermi level is very close to the conduction band edge and in the first
approximation two levels can be taken as equal. [19, 23] Therefore, measuring the quasi-
Fermi level allows the determination of the conduction band edge location of a
semiconductor under illumination. Only the quasi-Fermi level of electrons is easy
measurable for a semiconductor powder by pH-dependent photovoltage measurement. By
adding to this value the band-gap energy one obtains the valence band edge position.
Chapter 2. Al2O3 supported CdS
35
Figure 2.7: Electron and hole transfer at (a) large, (b) small semiconductor particles. [15]
The quasi-Fermi level for electrons (nEF*) was measured for the various photocatalysts.
Since the location of this level depends on the nature of the solvent, on the presence of ions
which adsorb on the semiconductor surface, and on the presence of surface states or surface
charge, the results of measurements must be given for a certain pH value and for the
solvent in which the measurement was carried out. All results of photovoltage
measurements in this work refer for aqueous suspensions at pH=7.
The quasi-Fermi levels for each photocatalyst were determined by photovoltage
measurements according to the method of Roy. [24] The photovoltage is the potential
difference vs. an auxiliary metal electrode (in our work it is a Pt flag) which is attained by
the illuminated semiconductor electrode in contact with a redox solution. [20]
Methylviologen, MV2+, was used as the pH-independent electron acceptor and pH
adjustment was performed by addition of HNO3 or NaOH (for experimental set-up and
procedure see also Experimental Section 6.2).
Chapter 2. Al2O3 supported CdS
36
E
ECB
EVB
nEF*
pEF*
EF
_
+
hν
E 0 E 0 E 0ECB
EVB
nEF*
pEF*
EF
_
+
hν
ECB
EVB
nEF*
pEF*
EF
_
+
hν
pH < pH0 pH = pH0 pH > pH0 Figure 2.8: Shift in band edge positions of the semiconductor during photovoltage
measurements with pH change. E0: redox potential of MV2+/+•, nEF*: quasi-Fermi level of
electrons under illumination, pEF*: quasi-Fermi level of holes under illumination.
At a given pH value the flatband position of the semiconductor is fixed at a certain value.
Upon decreasing the proton concentration, this position is shifted cathodically due to
negative surface charging induced by a decreased deprotonation. [18] However, the redox
potential of MV2+/+• is pH independent. Only when the flatband reaches the potential of
methyl viologen, reduction to the blue MV+• can occur. At this pH value (pH0) the quasi-
Fermi level potential is identical with the MV2+/+• redox potential. Measuring the
photovoltage at the various pH values affords titration curves and from the corresponding
inflection points (pH0) or second derivatives of pH-voltage curves, quasi-Fermi level
values were calculated. A blue color is developed at pH0 due to formation of MV+•. Values
were converted at pH=7 (vs. NHE) assuming that the potential change by 0.032 V [24] when
the pH-value is changed by one unit. Obtained titration curves are given in Figures 2.9-11
and corresponding data are presented in Table 2.4.
Chapter 2. Al2O3 supported CdS
37
Equations for calculating flat band potential of CdS at a required pH value are:
MV2+ + e- MV +
colourless blue
nEF*= EF(MV
2+/ MV
•+) (2.3.2.1)
nEF* = nEF
* (pH=0) - kpH (2.3.2.2)
nEF* (pH=0) – kpH = EF(MV
2+/ MV
•+) (2.3.2.3)
EF(MV2+
/ MV•+)= -0.445 V vs. NHE k = 0.032[24]
nEF* = -0.445 + 0.032(pH0 - 7) (2.3.2.4)
2 4 6 8 10 120
100
200
300
400
500
600
cb
V /
mV
pH
d
Figure 2.9: Dependence of photovoltage (vs. NHE) on pH value of the electrolyte
determined for (d) 10% CdS/Al2O3(n) [10NII], (c) 30% CdS/Al2O3(n) [30NII] and (b)
50% CdS/Al2O3(n) [50NII].
Chapter 2. Al2O3 supported CdS
38
2 4 6 8 10 120
100
200
300
400
500
600
c
ae
V /
mV
pH
Figure 2.10: Dependence of photovoltage (vs. NHE) on pH value of the electrolyte
determined for (e) 30% CdS/Al2O3(n) prepared in 25% NH3 [30NII25], (a) unsupported
CdS [CdS-A] and (c) 30% CdS/Al2O3(n) [30NII].
4 6 8 10 12
200
300
400
500
600
fh
V /
mV
pH
g
Figure 2.11: Dependence of photovoltage (vs. NHE) on pH value of the electrolyte
determined for acidic and basic Al2O3 supported CdS powders. (f) 30% CdS/Al2O3(a)
[30AII], (g) 10% CdS/Al2O3(a) [10AII], (h) 30% CdS/Al2O3(b) [30BII].
Chapter 2. Al2O3 supported CdS
39
Photocatalyst pH0 nEF*
[ + 0.01 V ]
CdS-A 7.89 -0.42
50NII 7.65 -0.42
30NII 8.05 -0.41
10NII 7.91 -0.41
30NII25 9.07 -0.38
10AII 9.50 -0.36
30AII 9.53 -0.36
30BII 9.84 -0.35
Table 2.4: pH0 and quasi-Fermi level values (mean of three independent measurements) of
alumina supported CdS powders at pH=7.
According to this result, while quasi-Fermi level stayed at a quite similar value for neutral
alumina supported powders prepared in 10% NH3, about 30 mV of anodic shift was found
for 30NII25. However, the anodic shift for acidic and basic alumina supported powders is
about 50 mV.
Figure 2.12 shows the dependence of quasi-Fermi level on pH according to Eq. 2.3.2.4.
0 2 4 6 8 10 12
-0,60
-0,45
-0,30
-0,15
nEF*
pH
Figure 2.12: Shift in quasi-Fermi level value per pH unit for 30NII.
Chapter 2. Al2O3 supported CdS
40
2.3.2.1. Quasi-Fermi Level Determinations In The Presence of Hole Scavengers
Photoexcitation of the semiconductor promotes an electron from the valence band to the
conduction band forming an electronic vacancy which is named as “hole” (h+) at the
valence band. For cadmium sulfide, this hole can be identified as an −•S or •SH radical. [12]
Scheme 2.1: Elementary processes during the photovoltage measurements
Photovoltage measurements for CdS powders were performed according to the method of
Roy [24] (for the theory of the method see Section 2.4.2, for experimental set-up and
procedure see also Experimental Section 6.2.1) in the absence of any hole scavenger as
mentioned above. However, the question arises which donor compound neutralizes the
hole. Therefore, quasi-Fermi levels were measured in the presence of hole scavengers like
CH3CO2Na and Na2SO3 by using 50NII (50% CdS/Al2O3(n)).
CdS + hν → CdS (e-CB h+
VB) absorption
CdS (e-CB h+
VB) → CdS recombination
CdS (e-CB h+
VB) + HOAc → CdS (e-CB) + CO2 + CH4 hole reaction
CdS (e-CB) + MV2+ → CdS + MV●+ electron trapping
MV●+ → MV2+ + e- oxidation
at collector (Pt) electrode
CdS + 2 h+VB → Cd2+ + “S“ photocorrosion
Chapter 2. Al2O3 supported CdS
41
Photocatalyst: 50NII
pH0
nEF* (at pH=7)
in the absence of a hole scavenger
(1st measurement)
(2nd measurement)
(3rd measurement)
7.55
7.92
7.65
-0.43
-0.42
-0.42
in the presence of Na2SO3 7.34 -0.43
in the presence of CH3CO2Na 7.05 -0.44
Table 2.5: Results of quasi-Fermi level measurements in the absence and presence of hole
scavengers for 50NII (50% CdS/Al2O3(n)).
Results are listed in Table 2.5. 1st-3rd measurement results were obtained from three
independent experiment in the absence of a hole scavenger in order to check the
reproducibility. The obtained values stay between -0.42 V and -0.44 V in the absence and
presence of hole scavengers. This suggests that using of a hole scavenger does not cause a
significant difference in the quasi-Fermi level. It is noted, however that the blue color of
MV+• is significantly more intense in the case of a hole scavenger.
The fact that the Fermi level measurement is not significantly influenced by the presence of
Na2SO3 or CH3CO2Na indicates that lattice SO32- ions are oxidized to polysulfides or
elemental sulfur. In order to test this hypothesis, attempts were made to identify elemental
sulfur, the expected photocorrosion product in the absence of oxygen. In the presence of
oxygen one expects SO42- formation. Sulfur and sulfate can be determined by XPS analysis
since the binding energy of the S2p electrons is about 161.5 eV for S2-, about 163.5 eV for
S0 and about 168 eV for SO42-. [25]
Determination of S0 by Photoelectron Spectroscopy (XPS)
In order to monitor a mutual S0 formation during photovoltage measurements, two
independent experiments were carried out in the absence of a hole scavenger with 50NII
(50% CdS/Al2O3(n)).
Chapter 2. Al2O3 supported CdS
42
2 4 6 8 10 12
200
300
400
500
600 b
3 6 9 12
-40
0
40
pH0 = 7.65
fII(U
)
pH
V /
mV
pH
a
Figure 2.13: Dependence of photovoltage on pH for 50NII (pH0= 7.65, nEF*: -0.42 V).
Preparation of samples for XPS:
Since it was expected that the XPS peaks corresponding to various sulfur species
mentioned above may overlap, two samples were prepared at early and late stages of the
redox titration.
I. Sample 1: To obtain the first sample the “titration” was stopped at pH 4.8 (pHinitial:
3.57; total irradiation time including voltage stabilization before the measurement:
1,5h) in order to prepare a sample from the beginning of the measurement (Figure
2.14 (a)). The CdS powder was filtered from the suspension carefully without
washing and dried under high vacuum (at RT).
II. Sample 2: In the second measurement the “titration” was stopped at pH 8.7 (pHinitial:
3.52) (Figure 2.14 (b)). After reaching this point, the pH value was kept constant and
irradiation was carried on for additional 4h (total irradiation time including voltage
stabilization before the measurement: 5h). Isolation of sample 2 was performed in the
same way like for sample 1.
Chapter 2. Al2O3 supported CdS
43
3,6 4,0 4,4 4,8
280
290
300
310
320
330
2 3 4 5 6 7 8 9 10 11 12
200
300
400
500
600
V /
mV
pH
V /
mV
pH
a
3 4 5 6 7 8 9
300
350
400
450
500
550
600
2 3 4 5 6 7 8 9 10 11 12
200
300
400
500
600
V /
mV
pH
b
V /
mV
pH
Figure 2.14: Dependence of photovoltage on pH in order to prepare (a) Sample 1 and (b)
Sample 2; 50NII.
Chapter 2. Al2O3 supported CdS
44
XPS Results
All samples were measured without sputtering. Peak fitting was performed with Gaussian
type curves for four XPS peaks of sulfur (2 for S2p1/2 and 2 for S2p3/2, respectively). %GL
means %Gaussian-Lorentzian parameter in the Gaussian-Lorentzian product function used
for peak optimization by XPSPeaks4.1® program. XPS curve fitting for untreated sample is
given in Figure 2.15. The best results were obtained with only two Gaussian type curves
for sulfur S2p1/2 and S2p3/2 locating peaks at about 161.2-162.3 eV which is in accord with
the binding energies for S2p electrons of S2- as reported in the reference [25]. The broad
signal shown in Figure 2.16 belongs to sample 1 which was prepared from the early stage
of the photovoltage measurement. In this case the peak could be fitted with four Gaussian
type curves (2 for S2p1/2 and 2 for S2p3/2). A little shift in peak position (161-162.5 eV)
and difference in peak shape were observed. Curve fitting was performed with four
Gaussian type curves (2 for S2p1/2 and 2 for S2p3/2) for sample 2 obtained from the late
stage of the photovoltage measurement (Figure 2.17). For this sample the peak was
broadened as compared to untreated sample and sample 1, and peak position shifted to
163.0 eV which is close to the literature value of 163.5 eV for S2p electrons of S0. [25] Such
broadening indicates the presence of elemental sulfur in sample after photovoltage
measurement and this suggests that in the absence of any hole scavenger, during the
photovoltage measurement anodic photocorrosion process works producing elemental
sulfur.
From this identification of S0 after photovoltage measurement, it is possible to conclude
that during a photovoltage measurement, in the absence of a hole scavenger (under
nitrogen), created holes upon irradiation are undergone photocorrosion:
CdS + h+ ⎯⎯→ Cd2+ + S−•
S−• + h+ ⎯⎯→ S0
Chapter 2. Al2O3 supported CdS
45
Figure 2.15: XPS curve fitting for untreated sample (before irradiation); 50NII.
Chapter 2. Al2O3 supported CdS
46
Figure 2.16: XPS curve fitting for sample 1 (total irradiation time including voltage
stabilization before the measurement: 1,5h); 50NII.
Chapter 2. Al2O3 supported CdS
47
Figure 2.17: XPS curve fitting for sample 2 (total irradiation time including voltage
stabilization before the measurement: 5h); 50NII.
Chapter 2. Al2O3 supported CdS
48
2.3.2.2. Investigation of Light Intensity Effect on Quasi-Fermi Level Determinations
Bard et al. reported earlier than Roy et al. that the quasi-Fermi level of a semiconductor
powder can be measured by photocurrent determination as a function of pH in the presence
of MV2+•. [26] They observed that the light intensity (irradiation source: 1600 W Xe lamp)
has a significant effect on the photocurrent; the photocurrent change with time (∆i/∆t)
increased linearly with increasing light intensity and they explained this behavior by Eq.
2.3.2.2.1 given below. According to this, the energy level of the electrons under
illumination, depends on the density of charge carriers initially present, no, and the excess
carriers generated by light, ∆n*. The increase of ∆n* with increasing intensity results in a
shift of the quasi-Fermi level of electrons to more negative potentials. They have assumed
that ∆n* is proportional to light intensity and this ratio (∆n*/no) is bigger than 1. Therefore,
the quasi-Fermi level of electrons becomes proportional to intensity.
nEF* = EF + kT ln [1 + (∆n* / n0)] (2.3.2.2.1)
In the case of an assumption that ∆n* is proportional to I and (∆n*/n0) >> 1, Eq. 2.3.2.2.1
can be written as
nEF* = constant + kT lnI (2.3.2.2.2)
In order to investigate if also the photovoltage method of Roy et al. exhibits a light
intensity effect, a series of experiments were performed. All measurements were carried
out with a 400 nm cut-off filter and various neutral density filters (%T: 70-12) to vary the
light intensity. A water bath between lamp and cuvette removed IR radiation. (For
experimental set-up see Experimental Section 6.2.2)
The experiments were performed with the alumina supported sample 50NII. Quasi-Fermi
level values of -0.38 V to -0.40 V were found (Table 2.6). These results show that
changing of the light intensity has no significant effect on the measurements because the
quasi-Fermi level values are within experimental error (Figure 2.18).
Chapter 2. Al2O3 supported CdS
49
The reason why in our photovoltage measurements no significant intensity effect was
observable, may stem from the much lower light intensity (150 W Xe lamp, λ ≥ 400 nm) as
compared to the experimental conditions of the Bard et al. experiments (1600 W Xe lamp).
Therefore, the change in electron concentration (∆n* / n0) is so small that the expected
change in the quasi-Fermi level (Eq. 2.3.2.2.1) can not be detected by the experimental
procedure applied.
Tranparency of filter T%
Light Intensity (I0) W/cm2
ln I0 pH0 nEF* [ ±0.01 V ]
100 0.29 -1.23 8.78 -0.39
70 0.17 -1.77 8.48 -0.40
50 0.13 -2.04 8.83 -0.39
43 0.09 -2.41 8.95 -0.38
35 0.085 -2.47 8.69 -0.39
28 0.08 -2.53 8.55 -0.39
12 0.03 -3.51 8.37 -0.40
Table 2.6: Dependence of pH0 and quasi-Fermi level values on light intensity; 50NII.
3,0 3,5 4,0 4,5 5,0 5,5 6,0
-0,8
-0,6
-0,4
-0,2
nEF*(
pH=7
) [V
vs.
NH
E]
lnI0
Figure 2.18: Plot of quasi-Fermi level values vs. normalized intensity (lnI0) revealing the
absence of any significant effect of change in light intensity; 50NII.
Chapter 2. Al2O3 supported CdS
50
2.3.2.3. Energetic Position of Band Edges for CdS/Al2O3 Photocatalysts
The knowledge of band edge positions is useful and important in photocatalysis because
these levels indicate the thermodynamic limitations for the photocatalytic reactions that can
be carried out with the charge carriers. As mentioned in Chapter 2.3.2, addition of the
band-gap energy to the value of the quasi-Fermi level, assumed to be equal to the
conduction band edge, gives the position of the valence band edge (Figure 2.19). The
values depicted there are the average mean of three independent measurements.
CdS-A 10NII 30NII25 30BII 30AII 10AII
2,5
2,0
1,5
1,0
0,5
0,0
-0,5 ⎯ ⎯ ⎯ ⎯ ⎯ ⎯
⎯ ⎯ ⎯ ⎯ ⎯ ⎯
2.462.432.412.482.452.39
+ 2.07+ 2.06+ 2.04+ 1.97 + 2.10+ 2.10
- 0.36- 0.36- 0.35- 0.38- 0.41- 0.42
Photocatalyst
E(F
B)[V
]
Figure 2.19: Band edge positions (+ 0.02 V) and band-gap energies (+ 0.01 eV) for CdS
photocatalysts at pH=7.
For the neutral alumina supported materials the conduction band edge position does not
change significantly, 60 meV and 90 meV of band-gap energy widening is observed for
10NII and 30NII25, respectively. The larger band-gap energy for 30NII25 may be due to
the increased concentration of surface [Al]-O- ions in more basic impregnation solution
which causes higher concentration of Cd-O-Al bonds (Chapter 2.2, Figure 2.2).
Chapter 2. Al2O3 supported CdS
51
Due to the band-gap widening, as compared to the unsupported CdS, an anodic shift of 70
mV and 130 mV in valence band edge position was observed for 10NII and 30NII25,
respectively.
When the acidic alumina was employed for supported CdS preparation, anodic shifts in
band edge positions (130 mV in valence band of 10AII, 100 mV in valence band 30AII,
and 60 mV in conduction band edge of both) and band-gap energy widening (40 meV for
30AII and 70 meV for 10AII) were observed (Figure 2.19).
In the case of basic alumina supported CdS, whereas the band-gap energy was identical
with the unsupported CdS, 70 mV and 90 mV of anodic shifts were observed in conduction
and valence band edges, respectively.
2.3.3. IR Spectra of Al2O3 Supported CdS Powders
When silica was alkylated before impregnation with cadmium ions, no SEMSI effect has
been observed. [27, 28] From this it is evident that the band-gap shift for silica supported CdS
powders originates from an electronic interaction between CdS and SiO2, which is induced
by formation of [Si]-O-Cd-S bonds through reaction of surface Si(OH) groups with Cd2+
ions. IR spectra show that the intensity of the OH absorption at 1190 cm-1 strongly
decreases. [27, 28] Contrary to this, the IR spectra of alumina supported CdS in KBr do not
show any obvious difference in the corresponding spectral region (very broad and smooth
band, in the range from 400 to 1000 cm-1 [29]). However, IR spectra of 30 wt% neutral
(Figure 2.20) and acidic (Figure 2.21) alumina supported CdS show that absorption bands
of support materials are shifted if CdS was supported with them. On the basis of the present
data no simple explanation can be given.
Chapter 2. Al2O3 supported CdS
52
4000 3500 3000 2500 2000 1500 1000 500
40
45
50
55
60
65
70
75
4000 3500 3000 2500 2000 1500 1000 500
40
50
60
70
80
90
100
586753
1628
3467
T%
cm-1
b
559
a
743
1647
3507T
%
cm-1
Figure 2.20: IR spectra of (a) neutral alumina and (b) 30% neutral alumina supported CdS
[30NII].
4000 3500 3000 2500 2000 1500 1000 500
50
55
60
65
70
75
4000 3500 3000 2500 2000 1500 1000 50070
75
80
85
90
95
578752
11331631
3464
T%
cm-1
b
a
568
753
1628
3441
T%
cm-1
Figure 2.21: IR spectra of (a) acidic alumina and (b) 30% acidic alumina supported CdS
[30AII].
Chapter 2. Al2O3 supported CdS
53
2.3.4. X-Ray Powder Diffractometry (XRD)
Al2O3 supported and unsupported CdS powders were analyzed by XRD (for instrumental
details, see Experimental Section 6.1.3.5) to determine their crystal modification and size
with the help of Scherrer equation (Eqs. 2.3.4.1 and 2.3.4.2). [30-32] Calculated grain size
values have been presented in Table 2.9.
Scherrer Equation:
L =0,9 . λ
FWHM . cosΘ
FWHM: the full width of the diffraction line at half maximum
Θ : the diffraction angle in degrees
λ : wavelength in A° (1.54 A° for copper)
(2.3.4.1)
Grain size = 4/3 L (2.3.4.2)
Measured diffraction angles and corresponding interplanar spacing (d, the distance between
crystal planes) values as calculated according to Bragg’s law (Eq. 2.3.4.3) for n= 1 are also
presented in Table 2.7 for CdS and Table 2.8 for Al2O3.
Bragg’s Law:
λ = wavelength in A° (1.54 A° for copper), n= 1
d = interplanar spacing in A° n λ = 2dsinΘ (2.3.4.3)
X-Ray powder diffractograms of alumina supported and unsupported CdS powders have
been given in the following. Diffraction peaks that marked with “ * ” and “ ο ” signs
indicate CdS and alumina, respectively.
Chapter 2. Al2O3 supported CdS
54
20 40 60 800
10
20 ***
Inte
nsity
2Θ [degrees]
CdS-A
*
Figure 2.22: X-ray powder diffractogram of CdS-A, (*) CdS.
20 40 60 800
10
20
30o
***
Inte
nsity
2Θ [degrees]
50NII
o
Figure 2.23: X-ray powder diffractogram of 50NII, (*) CdS, (°) Al2O3.
Chapter 2. Al2O3 supported CdS
55
20 40 60 800
10
20
30
40
o
o
o
***
Inte
nsity
2Θ [degrees]
30NII
Figure 2.24: X-ray powder diffractogram of 30NII, (*) CdS, (°) Al2O3.
20 40 60 800
10
20
30
40
50
60
o
o
o ***Inte
nsity
2Θ [degrees]
10NII
Figure 2.25: X-ray powder diffractogram of 10NII, (*) CdS, (°) Al2O3.
Chapter 2. Al2O3 supported CdS
56
20 40 60 800
10
20
oo
o
*
*
*
Inte
nsity
2Θ [degrees]
10AII
Figure 2.26: X-ray powder diffractogram of 10AII, (*) CdS, (°) Al2O3.
20 40 60 800
10
20
o oo *
*
* 30AII
Inte
nsity
2Θ [degrees]
Figure 2.27: X-ray powder diffractogram of 30AII, (*) CdS, (°) Al2O3.
Chapter 2. Al2O3 supported CdS
57
20 40 60 800
10
20
30
o o**
*In
tens
ity
2Θ
30BII
Figure 2.28: X-ray powder diffractogram of 30BII, (*) CdS, (°) Al2O3.
20 40 60 800
10
20
30
oo **
*
Inte
nsity
2Θ [degrees]
30NII25
Figure 2.29: X-ray powder diffractogram of 30NII25, (*) CdS, (°) Al2O3.
Chapter 2. Al2O3 supported CdS
58
Interplanar spacing (d) Values of Photocatalysts
(for diffraction peaks of CdS)
Photocatalysts 2θ 2sinθ d = λ/(2sinθ)
26.8 0.42 3.68
44.1 0.68 2.27 CdS-A
52.2 0.80 1.93
26.7 0.42 3.70
43.9 0.67 2.28
50NII
51.8 0.79 1.95
27.7 0.43 3.57
44.0 0.68 2.27
30NII
52.1 0.79 1.95
27.2 0.42 3.63
43.0 0.66 2.32
10NII
52.2 0.80 1.93
26.6 0.41 3.71
44.0 0.68 2.27
10AII
51.6 0.79 1.95
26.8 0.42 3.63
43.8 0.67 2.28
30AII
52.2 0.80 1.93
26.4 0.41 3.71
43.6 0.67 2.28
30BII
52.5 0.80 1.93
26.6 0.41 3.71
43.8 0.67 2.28
30NII25
52.2 0.80 1.93
Table 2.7: Diffraction angles and corresponding interplanar spacing (d) values calculated
according to Bragg’s law for various diffraction peaks of CdS.
Chapter 2. Al2O3 supported CdS
59
Interplanar spacing (d) Values of Photocatalysts
(for diffraction peaks of Al2O3)
Photocatalysts 2θ 2sinθ d = λ/(2sinθ)
37.1 0.57 2.68 50NII
67.1 1.00 1.53
37.2 0.58 2.67
45.6 0.70 2.20
30NII
67.1 1.00 1.53
37.3 0.58 2.67
45.4 0.70 2.20
10NII
67.0 1.00 1.53
37.6 0.58 2.67
45.6 0.70 2.20
10AII
67.2 1.00 1.53
36.9 0.57 2.68
46.1 0.71 2.17
30AII
67.2 1.00 1.53
38.0 0.59 2.62 30BII
67.1 1.00 1.53
37.2 0.58 2.67 30NII25
67.3 1.00 1.53
Table 2.8: Diffraction angles and corresponding interplanar spacing (d) values calculated
according to Bragg’s law for diffraction peaks of Al2O3.
Chapter 2. Al2O3 supported CdS
60
The 2Θ values of diffraction peaks observed at around 27°, 44° and 52° correspond to
(111), (220), and (311) Bragg reflection planes of cubic CdS, respectively. [33] In addition,
calculated d values also indicate a cubic β-CdS structure in accordance with ASTM-Card
No.-10-454 (d: 1.75, 2.06, 3.36). Therefore, from XRD analyses the cubic structure of CdS
powders was identified without ambiguity.
XRD analysis also identified γ-alumina structure by observation of typical diffraction peaks
of γ-alumina [29, 34] at 37°, 46° and 67°.
The average crystal sizes of CdS powders were calculated according to the Scherrer
equation [30-32] involving FWHM of the dominant (111) peak at about 2θ=26.6°. Taking of
the reflection at 26.6° is reasonable since only this peak does not suffer from the
interference of the reflections from γ-alumina. It is noted that this is a rough estimation.
Photocatalyst FWHM 2θ Particle size (nm)
CdS-A 2.5 26.8 7
50NII 2.4 26.7 8
30NII 2.4 27.7 8
10NII 2.2 27.2 9
10AII 2.5 26.6 8
30AII 2.6 26.8 7
30BII 2.5 26.4 8
30NII25 2.4 26.6 9
Table 2.9: The average crystal sizes of CdS powders obtained from the Scherrer equation.
From the calculated similar sizes of 8-9 nm, it is concluded that any observed band-gap
shift may not arise from a quantum size effect. XRD analysis also showed that cadmium is
present only as CdS on the surface of all photocatalyst powders.
Chapter 2. Al2O3 supported CdS
61
2.3.5. High Resolution TEM
To obtain some information on size, shape, and distribution of Al2O3 and CdS phases, TEM
analyses of CdS powders was perfomed. High resolution transmission electron micrographs
reveal that cubic and amorphous parts of CdS are present having nearly the same average
size of 10-20 nm (Figure 2.31). This agrees well with the values of 8-9 nm obtained from
XRD for the crystalline part.
50NII
Figure 2.30: The electron diffraction patterns of 50NII reveal the presence of the cubic
phase by observation of reflections from the (111), (220), and (311) planes.
Chapter 2. Al2O3 supported CdS
62
/ CdS-A / crystal size: 5-10 nm / 50NII / crystal size: 7-15 nm
/ 30NII / crystal size: 20-30 nm / 10NII / crystal size: >10 nm
Figure 2.31: HRTEM analyses of unsupported and supported CdS (10-50% alumina(n)).
Chapter 2. Al2O3 supported CdS
63
2.3.6. Interrogation of a Quantum-Size Effect
When the crystal size of a semiconductor decreases below a few nm (1-5 nm [35, 36]), band-
gap energy widening is observed. [37, 38] The presence of this effect in our materials can be
excluded since the crystal size of 8-20 nm is larger than the critical size and it does not
change with coverage as identified by XRD and HRTEM analyses.
2.3.7. X-Ray Photoelectron Spectroscopy (XPS)
XPS measurements were performed to determine the atomic species and the atomic
concentration of the CdS samples. Peak fitting was performed with Gaussian type curves
by the help of XPSPeaks4.1® program.
Figure 2.32: XPS peak fitting for S2p peak ([2] S2p1/2 and [1] S2p3/2) of CdS-A.
Chapter 2. Al2O3 supported CdS
64
Figure 2.33: XPS peak fitting for Cd3d peaks ([a] Cd3d3/2 and [b] Cd3d5/2) of CdS-A.
Chapter 2. Al2O3 supported CdS
65
For CdS, the valence band has S2p character whereas the conduction band is associated
with Cd3d. [39] Correspondingly, any change in the binding energy of Cd3d and S2p
electrons must be related with a shift in the level of conduction and valence band edge,
respectively.
Figure 2.34: XPS spectra of (a) Cd3d and (b) S2p in alumina supported and unsupported
CdS powders.
Chapter 2. Al2O3 supported CdS
66
Photocatalyst
Cd3d
[eV]
CB
[V]
S2p
[eV]
VB
[V]
Al2p (a)
[eV]
O1s (b)
[eV]
CdS-A 412.1 ; 405.4 -0.42 162.2 +1.97 - -
10NII 411.7 ; 405.0 -0.41 161.8 +2.04 74.75 531.39
10AII 412.1 ; 405.4 -0.36 162.2 +2.10 75.27 531.95
30NII25 411.9 ; 405.1 -0.38 162.0 +2.10 73.76 530.53
Table 2.10: Binding energies of alumina supported and unsupported CdS powders in
comparison with band edge values. (a)Al2p for Al2O3: 74.34 eV, (b) O1s for Al2O3: 531.03 eV.
As can be seen from Table 2.10, the maximum shift of Cd3d binding energies is 0.4 eV.
Similarly also S2p binding energies exhibit maximum shift of 0.4 eV. For detailed
discussion see Chapter 2.6).
From the data in Table 2.11, the ratio of Cd/Al concentration can be calculated.
Atomic Concentrations Photocatalyst
O S Cd Al
CdS-A 5.21 28.95 63.70 -
10NII 60.74 0.92 1.87 29.69
30NII25 58.74 2.47 5.57 26.66
10AII 58.42 1.87 4.23 28.80
Table 2.11: Atomic concentrations of Cd, S, Al and O in alumina supported and
unsupported CdS samples.
Chapter 2. Al2O3 supported CdS
67
Photocatalysts Atomic Cd/Al Concentration Ratio
10NII [(Cd: 1.87)/(Al:29.69)] = 0.063
30NII25 [(Cd: 5.57)/(Al:26.66)] = 0.209
10AII [(Cd: 4.23)/(Al:28.80)] = 0.145
Table 2.12: Atomic Cd/Al concentration ratios of alumina supported CdS samples.
The quite different Cd/Al ratio for two 10% supported catalysts 10NII and 10AII is
noteworthy (Table 2.12). According to elemental analysis the sample 10NII contains 8%
and 10AII 8.6% of CdS. This demonstrates that different to the overall composition, which
is almost identical for the two samples, the surface composition is quite different. In the
case of the sample prepared with acidic alumina (10AII), the amount of CdS on the surface
is more than two times higher. Therefore it is expected that light absorption by 10AII
should be more efficient than 10NII. The ratio of Cd/S for all catalysts is the same as it was
determined by XPS (Table 2.11).
Chapter 2. Al2O3 supported CdS
68
2.3.8. Time Resolved Photocharge (P-EMF) Measurements
The CdS photocatalysts were also characterized by time resolved photocharge (Photo-
Electromotive Force, P-EMF) measurements.
The principle of P-EMF measurements is based on formation of an inner electric field
between the dark and illuminated side of sample resulting from a spatial charge separation
because of different mobilities of electrons and holes generated by laser pulse exposure. [40]
This temporary potential difference causes a P-EMF (U, Dember-voltage) that can be
measured time-resolved (see Figure 2.36, 2.37, 2.38 and 2.39). From the sign of the
voltage, evidence for n- or p-type semiconductor behavior can be obtained. The life-time
allows conclusions to be made if a volume or surface recombination process is operating.
Charge separation due to diffrernt mobilities
of electrons and holes
Internal electric field
P-EMFCharge separation
due to diffrernt mobilities of electrons and holes
Internal electric field
P-EMF
Figure 2.35: Principle of P-EMF measurement technique.
Sample preparation was performed by dispersing CdS grains within a polymeric binder
(PWB Mowital B30 HH) (for experimental details, see Experimental Section 6.1.3.8). All
measurements are the average of three independent samples. Therefore, the P-EMF
parameters summarized below are the mean values of three measurements.
Heterojunctions may cause internal electric fields. If the lifetime of the charge carriers
generated by the laser flash is sufficiently long, these internal electric fields can alter the P-
EMF signal with increasing number of laser flashes. To avoid such influences only the
signal of the first laser flash was recorded. Under the measurement conditions (Nitrogen
laser flash, λ=337 nm, about 2.7x1013 quanta/flash), all samples exhibit total absorption.
Since the measurements were applied for CdS-A, 50NII, 30NII, 10NII as one set of
measurement and for 30AII, 30NII25, 30NII as another set, the sample 30NII was
included in the second set to make the results from these two sets comparable.
Chapter 2. Al2O3 supported CdS
69
In order to obtain information on the complete decay process, P-EMF measurements were
performed in two time scales; a µs range for the fast, a ms range for the slow decay
processes. For the kinetic evaluation of the P-EMF-signals, a biexponential rate law (Eq.
2.3.8.1) was applied.
( ) ( ) ( )U t U k t U k t= ⋅ − + ⋅ −10
1 20
2exp exp (2.3.8.1)
Moreover, from the experimental curve the maximum P-EMF Umax was determined. The
calculated values of the partial P-EMFs (U10 for surface and U2
0 for bulk in the
photoconducting material) were normalized to Umax by using Eqs. 2.3.8.2 and 2.3.8.3:
U U Umax = +10
20 (2.3.8.2)
U UUU
norm20
10
201
,max
,exp.
,exp
=+
(2.3.8.3)
The sum of the partial P-EMFs (U10 and U2
0) corresponds to the Umax (maximum P-EMF,
Eqs. 2.3.8.1 and 2.3.8.2). Under pulse illumination (t=0, at the beginning of the
measurement), P-EMF reaches a maximum value (U= Umax) followed by a decay, which is
caused by recombination of the generated charge carriers (see Figure 2.36-39). In the case
of both time ranges, k values indicate surface recombination (k1) and bulk recombination
(k2). In another words, measuring of k1 and k2 values gives lifetime (τ) values because of
τ=1/k relation, in the surface and in the bulk of the photoconducting material, respectively.
All investigated CdS samples show P-EMF signals starting with a positive sign indicating
that all samples behave as n-type photoconductors. The type of photoconduction is not
altered by the support materials.
Chapter 2. Al2O3 supported CdS
70
For all samples the P-EMF decay process shows a broad rate distribution which is caused
by a broad trap depth distribution. For that reason the biexponential rate law is only an
approximation for describing the P-EMF decay. But the parameters from the biexponential
rate law can be used for a comparison of the P-EMF decay rate in a given time range. The
P-EMF decay rate constants measured in the µs time range reflect the release of charge
carriers from shallow traps and their recombination, and in the ms time scale the release of
charge carriers from deeper traps and their recombination.
The P-EMF signals of CdS-A and 10-50% CdS/Al2O3(n) are presented in Figures 2.36 and
2.37. Corresponding parameters are summarized in Tables 2.13 and 2.14.
For all samples, Umax values decrease with increasing alumina to CdS ratio. It is known that
coating or mixing of a photoconductive material with a photoelectrically inactive material
decreases the value of Umax. [40, 41] Since in the same direction (of increasing Al2O3/CdS
ratio) the amount of CdS decreases, the voltage decrease may additionally stem from a
diminished light absorption.
The amount of CdS on Al2O3 also influences the P-EMF decay rate. On the µs -time scale
the P-EMF decay rate of 50NII sample is very close to that of unsupported CdS-A. For
30NII and 10NII, the P-EMF decay becomes gradually slower. That means the lifetime of
charge carriers is influenced by interactions between CdS and the neutral Al2O3 support.
Chapter 2. Al2O3 supported CdS
71
0,0 0,5 1,0 1,5 2,0 2,5
0
10
20
30
40
50
60
70
10NII
30NII
50NII CdS-A
Phot
o-EM
F U
/ m
V
time t / µs
Figure 2.36: P-EMF signals of unsupported CdS (CdS-A) and neutral alumina supported
CdS samples recorded up to 2.5 µs after the laser flash (λexc = 337 nm).
SAMPLE Umax [mV] U10 [mV] U2
0 [mV] k1 [x106 s-1] k2 [x104 s-1]
10NII 26.9±1.9 7.6±0.9 19.3±2.1 0.80±0.24 1.87±0.06
30NII 40.5±2.8 6.6±0.8 33.9±3.7 1.16±0.04 1.04±0.03
50NII 46.2±3.2 8.6±1.0 37.6±4.2 1.34±0.04 1.18±0.04
CdS-A 67.3±4.7 26.8±3.0 40.5±4.5 1.32±0.04 1.95±0.06
Table 2.13: Umax values and kinetic parameters of the P-EMF signals shown in Figure
2.36.
Chapter 2. Al2O3 supported CdS
72
0 50 100 150 200-5
0
5
10
15
20
25
30
10NII 30NII 50NII CdS-A
Phot
o-E
MF
U /
mV
time t / ms
Figure 2.37: P-EMF signals of unsupported CdS (CdS-A) and neutral alumina supported
CdS samples recorded up to 200 ms after the laser flash (λexc = 337 nm).
SAMPLE Umax [mV] U10 [mV] U2
0 [mV] k1 [s-1] k2 [s-1]
10NII 11.9±0.9 14.2±1.6 -2.3±0.3 153±1.5 20.4±0.2
30NII 24.1±1.7 31.6±3.5 -7.5±0.9 109±1.1 23.7±0.2
50NII 27.4±1.9 37.6±4.2 -10.2±1.1 98.1±1.0 24.1±0.3
CdS-A 23.4±1.6 34.4±3.8 -11.0±1.2 101±1.0 29.8±0.3
Table 2.14: Umax values and kinetic parameters of the P-EMF signals shown in Figure
2.37.
Chapter 2. Al2O3 supported CdS
73
Although there is no direct evidence that the lifetime of the surface charge carriers
determined by P-EMF is that of the reactive e- - h+ pair, this plausible approximation is
made in the following discussion. Table 2.15 summarizes the corresponding rate constants,
lifetimes and band-gap energies.
Sample k1 [x106 s-1] τ1 [x10-6 s] Ebg [± 0.01 eV]
10NII 0.80±0.24 1.20 2.45
30NII 1.16±0.04 0.86 2.43
50NII 1.34±0.04 0.75 2.42
CdS-A 1.32±0.04 0.76 2.39
Table 2.15: Calculated lifetimes from k values (τ = 1/k) and measured band-gap energy
values for unsupported CdS and CdS supported onto neutral alumina.
From these it can be seen that the increase of band-gap energies with decreasing coverage
is accompanied by a lifetime increase. This larger lifetime should increase electron
exchange rates with adsorbed substrates. The results of photocatalytic activity
measurements are discussed together with the results of P-EMF measurements in Chapter
2.4.2.
The P-EMF signals of three supported samples containing all 30wt% of CdS but have been
prepared under slightly different conditions are presented in Figure 2.38 in µs time range
and Figure 2.39 in ms range. The parameters of the P-EMF signals shown in Figure 2.38
and 2.39 are summarized in Table 2.16 and 2.17.
Chapter 2. Al2O3 supported CdS
74
0 20 40 60 80 100
0
5
10
15
20
25
30NII30AII
Phot
o-E
MF
U /
mV
time t / µs
30NII25
Figure 2.38: P-EMF signals of 30 wt% CdS on Al2O3 samples recorded in the time range
up to 100 µs after the laser flash (λexc = 337 nm).
SAMPLE Umax [mV] U10 [mV] U2
0 [mV] k1 [x105 s-1] k2 [x103 s-1]
30AII 20.2±0.2 6.6±0.1 13.6±0.1 1.74±0.13 3.08±0.09
30NII 22.6±0.2 9.5±0.1 13.1±0.2 1.63±0.08 4.56±0.09
30NII25 23.2±0.1 2.8±0.1 20.3±0.2 1.56±0.01 1.18±0.01
Table 2.16: Umax values and kinetic parameters of the P-EMF signals shown in Figure
2.38.
Chapter 2. Al2O3 supported CdS
75
0 50 100 150 200-3
0
3
6
9
12
15
18
30AII 30NII 30NII25
Phot
o-E
MF
U /
mV
time t / ms
Figure 2.39: P-EMF signals of 30 wt% CdS on Al2O3 samples recorded in the time range
up to 200 ms after the laser flash (λexc = 337 nm).
SAMPLE Umax [mV] U10 [mV] U2
0 [mV] k1 [s-1] k2 [s-1]
30AII 8.9±2.0 13.6±1.9 -4.7±0.9 130±15 41.6±2.0
30NII 9.0±4.7 10.4±5.2 -1.5±0.5 226±20 31.9±2.5
30NII25 17.8±1.5 1991±491 -1973±490 56.4±0.4 55.9±0.4
Table 2.17: Umax values and kinetic parameters of the P-EMF signals shown in Figure
2.39.
Chapter 2. Al2O3 supported CdS
76
The P-EMF of samples on the acidic (30AII) or neutral Al2O3 (30NII) supports decay
faster than that of the CdS sample which was prepared in more basic solution with neutral
Al2O3 (30NII25) (Table 2.16). This means the properties of the support material or
preparation method govern the charge carrier lifetimes.
Band-gap energy values and lifetime values for 30wt% supported CdS powders were listed
in Table 2.18.
Sample k1 [x105 s-1] τ1 [x10-5 s] Ebg [± 0.01 eV]
30AII 1.74±0.13 0.57 2.43
30NII 1.63±0.08 0.61 2.43
30NII25 1.56±0.01 0.64 2.48
Table 2.18: Calculated lifetimes from k values (τ = 1/k) and band-gap energy values for
30wt% CdS on Al2O3(n), and Al2O3(a).
Increasing NH3 concentration from 10% to 25% affords 30NII25 which leads to a larger
band-gap energy (2.48 eV vs. 2.43 eV) whereas the increase in lifetime is not significant.
Different from this, supported 30% CdS onto acidic alumina (30AII) does not influence the
band-gap that decreases the lifetime from 6.1 to 5.7 µs. A similar increase of lifetime with
increasing band-gap energy is observed in the sequence from 50NII over 30NII to 10NII
samples. (The results of photocatalytic activity measurements are discussed together with
the results of P-EMF measurements in the following Section 2.4.2).
Chapter 2. Al2O3 supported CdS
77
2.4. Photocatalytic Activity of Al2O3 Supported CdS
2.4.1. Determination of the Optimum Photocatalyst Amount
Since the absorption properties of the various photocatalysts are not identical because of
their different CdS coverage, first of all it was necessary to eliminate this concentration
effect which may cause a wrong consequence in photocatalytic activity comparisons. To
determine for each catalyst the total amount of material exhibiting the same light
absorption, the KM function was measured at 490 nm by diffuse reflectance spectroscopy
(DRS).
The DRS method was mentioned in Section 2.3.1 as a useful technique for non-transparent
solid materials and it is defined as a type of absorption spectroscopy. [42, 43] According to
literature (see also Section 2.3.1) the logarithm of the KM function is proportional to the
absorption coefficient (k in Eq. 2.4.1.1).
log F(R∞) = log(k) – log(s) (2.4.1.1)
Since the scattering coefficient (s in Eq. 2.4.1.1) very often does not depend substantially
on λ [41], Eq. 2.4.1.1 can be written as
log F(R∞) = log(k) – constant (2.4.1.2)
In order to determine for each catalyst the amount necessary to induce the same KM
function, a series of DRS measurements were performed. KM values at 490 nm were
measured for different concentrations for each photocatalyst by changing its concentration
in BaSO4. After determination of KM values for each dilution, KM values were plotted vs.
catalyst amount (e.g. for 30NII Figure 2.40). Table 2.19 summarizes the amount of
catalysts exhibiting identical KM function. As a first approximation it is assumed that for
all these materials present in this optimum concentration, the amount of light absorbed is
identical.
Chapter 2. Al2O3 supported CdS
78
The corresponding diluent was also used as the baseline standard. Usage of BaSO4 as
diluent can be thought as the counterpart of alumina because as it has been depicted in
Section 2.3.1, using one of these two materials does not have any influence on the
measurement.
In addition, since it was reported in the literature that in the case of some semiconductors,
dilution of the material in weak or non-absorbing standards may cause a blue or in some
cases red shifts in the band-gap energy value. [44] Therefore, for each dilution, band-gap
energy values were also inspected whether if they vary or not. However, after every
dilution step band-gap energy values of powders did not vary by dilution.
0,4 0,6 0,8 1,0 1,2 1,4 1,60,0
0,5
1,0
1,5
2,0
2,5 30NIIslope: 1.76
amount of catalyst [g]
KM
at 4
90 n
m
Figure 2.40: Relation between KM and catalyst concentration for the example of 30NII.
Photocatalyst Amount of Photocatalyst [g]
CdS-A 0.51 50NII 0.77 30NII 0.77 10NII 1.44 30AII 0.77 10AII 0.91
30NII5 0.86
Table 2.19: Amount of photocatalysts (g) exhibiting a KM value of 1.
Chapter 2. Al2O3 supported CdS
79
2.4.2. Photocatalytic Activity Measurements
In order to compare photocatalytic activities of CdS photocatalysts, the addition of
cyclopentene to N-(4-chlorobenzylidene)-4-chloraniline was carried out since many
mechanistic investigation have been previously performed with this system.
C N
H
Ar
Ar
MeOH
C N
H
H
Ar
ArCH
CHAr NHAr
Ar NHAr+
CdS/hν+
C NH
H
Ar
Ar
- H+
H+
er-
hr+
Figure 2.41: CdS-photocatalyzed addition of cyclopentene to N-(4-chlorobenzylidene)-4-
chloraniline. [45] (Ar: 4-ClC6H4)
Photocatalyst Photocatalyst concentration exhibiting KM=1 at 490 nm
[g / 100g of BaSO4]
Photocatalyst concentration taken for rate determination(a)
[g/l] CdS-A 25.5 1.8
50NII 38.5 2.7
30NII 38.5 2.7
10NII 72.0 5.0
30AII 38.5 2.7
10AII 45.5 3.3
30NII25 43.0 3.1
Table 2.20: Amount of photocatalyst exhibiting identical KM values, (a) calculated
according to Table 2.19.
Chapter 2. Al2O3 supported CdS
80
The reaction was carried out in a round cuvette placed on an optical bench under nitrogen
atmosphere with full-light irradiation (for detailed experimental set-up, see Experimental
Section 6.4). Photocatalyst concentration was taken according to determined optimum
catalyst concentration (Table 2.20) as explained in Section 2.4.1. Initial consumption rate
of the imine substrate was determined by HPLC analysis.
CdSA 50N 30A 30N 10N 10A 30N25
0,2
0,4
0,6
0,8
1,0
1,2
1,4
1,6
1,8
2,0
2,2
Rea
ctio
n R
ate
/ 10-7
mol
l-1s-1
PhotocatalystCdSA 50NII 30AII 30NII 10NII 10AII 30NII25
Figure 2.42: Photocatalytic activities of alumina supported CdS photocatalysts in
comparison with unsupported CdS.
As can be seen from Figure 2.42 in the case of neutral alumina as support, the reaction rate
increases by about 40 and 120% when the coverage is decreased from 50% to 30% and
10%, respectively. When the concentration of ammonia solution was increased from
usually employed 10% to 25%, the reaction rate increased by 440%.
Chapter 2. Al2O3 supported CdS
81
For acidic alumina at 30% loading, the rate is the same as for the neutral supported one but
it increased by 87%.
The variation of reaction rate as a function of coverage correlates with the increased
lifetime of charges as measured by P-EMF (Table 2.21). This increased lifetime may
originate in the band-gap widening of 30, 40, and 60 meV when comparing 50, 30, and
10% coverage with unmodified CdS. In the same sequence the CB edge is not significantly
changed whereas the VB edge is anodically shifted by 30, 50, and 70 mV.
Photocatalyst Ebg
[eV]
CB
[V]
VB
[V]
Lifetime
[10-6 s]
Reaction Rate
[10-7 moll-1s-1]
CdS-A 2.39 -0.42 +1.97 0.76 0.24
50NII 2.42 -0.42 +2.00 0.75 0.25
30NII 2.43 -0.41 +2.02 0.86 0.36
10NII 2.45 -0.41 +2.04 1.20 0.84
Table 2.21: Band edge positions, band-gap energies and lifetime values of unsupported
CdS and 10-50%CdS/Al2O3(n) in comparison with reaction rates.
When the photocatalysts are compared which all contain 30% of CdS, the change again a
correlation between lifetime and reaction rate is observed (Table 2.22).
Photocatalyst
Ebg
[eV]
CB
[V]
VB
[V]
Lifetime
[10-5 s]
Reaction Rate
[10-7 moll-1s-1]
30AII 2.43 -0.36 +2.07 0.57 0.34
30NII 2.43 -0.41 +2.02 0.61 0.36
30NII25 2.48 -0.38 +2.10 0.64 1.97
Table 2.22: Band edge position, band-gap and lifetime values in comparison with reaction
rates of 30wt% Al2O3 supported CdS photocatalysts.
Chapter 2. Al2O3 supported CdS
82
Significant difference in photocatalytic activity between 10AII and 10NII is also
considerable. According to elemental analysis the sample 10NII contains 8% and 10AII
8.6% of CdS. Data presented in Table 2.23 demonstrates that different to the overall
composition, which is almost identical for the two samples, the surface composition is quite
different. In the case of the sample prepared with acidic alumina (10AII), the amount of
CdS on the surface is more than two times higher (0.06 vs. 0.14). Whereas aluminum
amount is almost the same (about 29-30), such a difference in Cd/Al ratio may cause more
efficient light absorption by 10AII than 10NII. Accordingly, quite higher reaction rate for
10AII is reasonable.
Photocatalysts %CdS(a) Atomic Cd/Al
Concentration Ratio(b)
Reaction Rate
[10-7 moll-1s-1]
10NII 7.8 [(Cd: 1.87)/(Al:29.69)]
0.06
0.84
10AII 8.6 [(Cd: 4.23)/(Al:28.80)]
0.14
1.47
Table 2.23: Atomic Cd/Al concentration ratios, %CdS amounts of 10wt% acidic (10AII)
and neutral (10NII) alumina supported CdS samples in comparison with reaction rates.
(a) Obtained from the elemental analysis, (b) Obtained from XPS analysis.
Chapter 2. Al2O3 supported CdS
83
2.5. Comparison of Al2O3 with SiO2 as Support Material for CdS
In thermal heterogeneous catalysis the influence of supports on the catalytic properties of
noble metal particles, may result in an increase in the turnover frequency (TOF) on acidic
supports and a decrease on alkaline supports. [46-50] These changes in catalytic properties
are generally ascribed to a modification of electronic properties of the metal particles
resulting from a metal–support interaction. [46, 51] From all this work three methods have
aroused in order to explain the interaction.
The first method suggests that there is a partial electron transfer between the metal and the
oxide ions of the support. Acidic supports withdraw electron density from the metal,
whereas alkaline supports donate electron density to the metal and changes in catalytic and
spectroscopic properties result from a change in the number of electrons in the valence
orbitals. Briefly, metals are electron deficient on acidic supports and electron rich on
alkaline supports. [47-49, 52]
The second model proposes an interaction between support protons and the metal particles
forming metal–proton adducts. According to this proposal, the delocalized proton over the
metal particle withdraws electron density from the surface atom. [52, 53]
These two models compromise in that they both propose that there is a transfer of electron
density due to the metal–support interaction. However, they differ in that in the former the
transfer is thought to occur between the metal and the support oxide ions, while in the latter
the metal transfers electron density to the support protons. [46] In both cases, the increase in
catalytic activity has attributed to electron deficiency of metal on acidic supports.
Therefore, there is a change in the number of electrons in the valence orbital of the metal
that causes changes in catalytic and also spectroscopic properties of the supported catalyst.
The third method proposes a shift in the metal (Pt in depicted work) valence band (Pt5d)
instead of the transfer of electron density between the metal particle and the support. [46]
According to this expression, the change in the charge density of the support oxide ions
related with the acidity induces a shift in the energy of the metal valence orbitals, rather
than a change in the number of valence electrons. This proposal based on obtained
evidence from near-edge spectra (so called VB spectra) indicating little difference between
various supported metal catalyst. However, the shape resonance of the Pt-H antibonding
Chapter 2. Al2O3 supported CdS
84
orbital was strongly influenced, i.e. the difference in energy between the Fermi level and
antibonding orbital (ERes) was changed, by the acidic or alkaline properties of the support.
The explanation of this observation expressed in the following.
Figure 2.43: Molecular orbital diagram of the bonding and antibonding orbitals for the Pt
valence and the H 1s orbitals with changing support composition. [46]
The energy of the H1s orbital is lower than the energy of the Pt valence orbitals. Since the
energy of the H1s bonding orbital does not change with catalyst composition, the observed
change in the difference between the Fermi level and the antibonding orbital results from a
shift in the energy of the Pt valence orbitals due to the interaction with the support. [46] In
conclusion, the more similar the energy of the Pt and H orbitals the stronger is the bond and
greater is the difference in energy between the Pt-H antibonding orbital and the Fermi level
which means a larger ERes. Larger ERes indicates stronger overlap of the bonding orbitals
and a shift to higher binding energy of the metal valence orbitals (see Figure 2.43).
Chapter 2. Al2O3 supported CdS
85
Based on the EXAFS (extended X-ray absorption fine structure) results [54], it has been also
concluded that the shift in the energy of the valence band orbitals results from an
interaction of the metal with the support oxide ions. According to this, the higher the
negative charge on the oxygen, the smaller is the decrease in energy (lower binding energy)
of the metal valence orbitals. As the electron density of the support oxide deceases or
becomes more acidic, the binding energy of the metal valence orbitals increases. [46]
Electronic semiconductor-support interaction was firstly reported for silica (Grace Typ
432) supported CdS as a novel effect in photocatalysis that originates basically from Cd-O-
Si bonds. [28] It was assumed that the widening therefore increases with increasing density
of surface OH groups. Experimental evidence for this assumption was based on the fact
that a silica support that contained n(OH) = 14.0/nm2 as compared to n(OH) = 10.5/nm2. [27]
In order to get more experimental evidence for these previous observations, two sets of
experiments were performed. In the first one, the recently used silica support (Grace Typ
432) was employed to prepare 30% CdS/SiO2 and the band-gap energy was measured. A
value of 2.53 eV was obtained which is in accord with the recent findings (see also
references [27, 28]). This support has a 308 m2/g specific surface area and the other
(Aerosil) 148 m2/g (Table 2.24). To check whether the specific surface area has a
significant influence on the SEMSI effect, in the second set of experiments a silica support
(Aerosil) was selected that possessed about the same OH density but only half of the
specific surface area.
Surprisingly, this material exhibited a band-gap energy of 2.48 eV (Figure 2.44, 30%
CdS/SiO2 (Aerosil)) which was 50 meV difference as compared with the higher surface
area support. In addition, band-gap widening was rather smaller for Aerosil type silica as
compared to Grace type. Whereas the coverage varies from 50% over 30% to 10%, band-
gap energy values differs as 2.43, 2.48, and 2.50 eV, respectively.
Chapter 2. Al2O3 supported CdS
86
2,1 2,2 2,3 2,4 2,5 2,60
50
100
150
200
dbc a
[F(R
∞)h
ν]2
hν / eV
Figure 2.44: Transformed diffuse reflectance spectra of Aerosil SiO2 supported CdS
powders.
(a) 50% CdS/Al2O3(Aerosil) [50AE] (Ebg: 2.43 + 0.01 eV), (b) 30% CdS/Al2O3(Aerosil)
[30AE] (Ebg: 2.48 + 0.01 eV), (c) 10% CdS/Al2O3(Aerosil) [10AE] (Ebg: 2.50 + 0.01 eV),
(d) 30% CdS/Al2O3(Aerosil) prepared in 25% NH3 [30AE25] (Ebg: 2.52 + 0.01 eV).
Preparation of 30% Aerosil silica supported CdS in the more basic 25% ammonia solution
afforded a larger band-gap material (Figure 2.44); the same effect has been also observed
for alumina supported catalysts. Such an influence of the more basic preparation medium
can be explained as follows. Due to the increased concentration of surface [Si]-O- ions, the
equilibrium (see Chapter 2.2, Figure 2.2) should be shifted to the right side and therefore
the concentration of Cd-O-Si bonds should be increased. In the case of alumina as support
the same influence of a more basic impregnation solution is observed (see Section 2.3.1).
Chapter 2. Al2O3 supported CdS
87
Within the different alumina supported materials such a comparison is not related only with
the OH group density but also with the specific surface area. Whereas the specific surface
areas of acidic alumina (150 m2g-1) and basic alumina (146 m2g-1) are almost identical, the
higher OH group density of the acidic one (see Table 2.24) does not lead to a significant
shift in the band-gap energy. Similarly, in the case of the same OH group densities for
basic and neutral alumina supports, the larger specific surface area of the neutral one does
not have a significant influence (see Table 2.24).
Nevertheless, another question remains: what is the difference between alumina and silica
that leads to a more efficient electronic interaction in the case of silica. As already noted
the difference in OH group densities and specific surface areas (Table 2.24) do not
correlate.
Support Material n(OH)/nm2 Specific Surface Area
[m2g-1]
Ebg [ + 0.01 eV ]
for 30% supported
CdS
SiO2 Grace Typ 432 1.7 308 2.53
SiO2 Aerosil 200 1.6 148 2.48
Al2O3 Aldrich, neutral 3.8 189 2.43
Al2O3 Aldrich, acidic 6.2 150 2.43
Al2O3 Aldrich, basic 4.3 146 2.41
Table 2.24: Specific surface areas, surface OH group densities of Al2O3/SiO2 support
materials and band-gap energies for 30wt% supported CdS.
From the data presented above, one can conclude that increasing the acidity of support
(comparison of the acidic silica with the neutral and the acidic alumina) increases the band-
gap energy and thus indicates a stronger SEMSI effect. Since this effect originates from
Cd-O-M bonds (M: Si or Al), any change of their electronic nature is expected to influence
the position of conduction and valence band edges. It is recalled that the former has Cd
character, the latter S character.
Chapter 2. Al2O3 supported CdS
88
Changes in conduction band edge can be monitored by measuring the quasi-Fermi level of
electrons or the Cd3d binding energy. In the case of silicon which has a higher
electronegativity (1.74) than aluminum (1.47), one expects a decreased electron density on
Cd and therefore a higher Cd3d binding energy. In accord with this the band-gap widening
in the case of silica supported materials is 180 meV as compared to 50 meV for neutral
alumina supported materials. When the influence of various alumina supports is
considered, one does not observe a simple correlation, however (Table 2.25). Whereas the
Cd3d binding energy is almost the same for unsupported CdS and CdS supported by
neutral and acidic alumina, the conduction band edge shifts by 40 to 60 mV anodically. The
similar trend was observed for the valence band and although S2p binding energy values do
not vary significantly, the valence band shifts by 70 to 130 mV (Table 2.25). Since the
semiconductor-support interaction between alumina support and CdS was not so
significant, the slight anodic shifts in band edge positions were observed only by the quasi-
Fermi level determinations. Thereupon, determined changes in binding energy values differ
only in small ranges.
Photocatalyst Cd3d
[eV]
CB
[V]
S2p
[eV]
VB
[V]
CdS-A 412.1 ; 405.4 -0.42 162.2 +1.97
10NII 411.7 ; 405.0 -0.41 161.8 +2.04
10AII 412.1 ; 405.4 -0.36 162.2 +2.10
30NII25 411.9 ; 405.2 -0.38 162.0 +2.10
Table 2.25: Cd3d binding energy values of alumina supported and unsupported CdS
powders in comparison with conduction band level.
Chapter 2. Al2O3 supported CdS
89
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[51] D. C. Koningsberger, J. de Graaf, B. L. Mojet, D. E. Ramarker, J. T. Miller, Applied
Catalysis A: General 2000, 191.
[52] W. M. H. Sachtler, A. Y. Stakheev, Catal. Today 1992, 12, 283.
[53] S. T. Homeyer, Z. Karpinski, W. M. H. Sachtler, J. Catal. 1990, 123, 60.
[54] D. E. Ramaker, B. L. Mojet, M. T. Garriga Oostenbrink, J. T. Miller, D. C.
Koningsberger, Phys. Chem. Chem. Phys. 1999, 1, 2293.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
92
CHAPTER 3 3. CdS-Photocatalyzed Synthesis of Novel Homoallylamines
3.1. Photocatalytic Addition Reactions with N-Cinnamylideneaniline
3.1.1. Photocatalytic Addition Reactions of N-Cinnamylideneaniline with
cyclopentene, cyclohexene and α-pinene
Ph NPh
R-H
MeOH
Ph NH
Ph
R
Ph NH
Ph
Ph NH
Ph
R
+30% CdS/Al2O3
addition at α-position to the imin function
addition at γ−position to the imin function
hν
R:Me
6 a-c
7a-c 8a-c
a b c
Figure 3.1: CdS-photocatalyzed linear addition of olefins to N-Cinnamylideneaniline
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
93
Irradiation of a methanolic solution of N-Cinnamylideneaniline in the presence of 30%
CdS/Al2O3(n) as a photocatalyst and an excess (40 fold) of olefin produces novel
homoallylic secondary amines (Figure 3.1), which are a C-C coupling product between the
α-amino cinnamyl radical generated from the imine and allylic radical formed from olefins.
The reaction was carried out under N2 atmosphere in a Pyrex immersion lamp apparatus
(see Experimental Section 6.1.1, Figure 6.1) equipped with a 100W tungsten halogen
lamp. Reaction progress was followed by HPLC and TLC analysis. After complete
consumption of 6, irradiation was stopped, the catalyst was filtered off, and the solvent was
removed under reduced pressure. Product mixtures were obtained as dark yellow oils in
every case. Purification by preparative column chromatography packed with neutral
alumina provided the addition products as yellow oils in the yields of 48-72%. All work-up
processes including catalyst filtration, solvent evaporation, TLC and preparative column
chromatography steps were performed under N2 because of high air sensitivity of the
compounds. The lowest isolated product yield of 48% belongs to the α-pinene addition
product, due to its decomposition during the irradiation process before complete
consumption of 6 as observed by HPLC.
3.1.1.1. HPLC Analysis
Figure 3.2 illustrates the progress of the reaction between olefins and 6 followed by HPLC.
Appearance of new peaks at 38 and 40.5 minutes for cyclopentene (Figure 3.2 (b)), at 49
and 52 minutes for cyclohexene (Figure 3.2 (c)), and at 47 and 49 minutes for α-pinene
(Figure 3.2 (d)) addition to 6 indicates formation of diastereomeric mixture of 7a, 7b, and
7c, respectively. The peak at around 14 minutes in each chromatogram belongs to 6.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
94
Figure 3.2: HPLC-Analysis of CdS-photocatalzed addition of olefins to 6 (detection at
254 nm, eluent: CH3CN/H2O=70/30 (v/v), for the instrumental set-up see Experimental
Section 6.1.3.12). (a) Before irradiation, (b) Addition of cyclopentene (after 40 h of
irradiation), (c) Addition of cyclohexene (after 20 h of irradiation), (d) Addition of
α-pinene (after 12 h of irradiation).
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
95
As already discussed, the consequence of proton coupled IFET is the formation of an
intermediate α-amino cinnamyl radical from 6 and an allylic radical from the olefin.
Hetero-C-C coupling leads to two stereogenic centers in the addition products (Figure 3.3).
NH
H
PhPh
R
R
NH
H
PhPh
R
HN
H Ph
Ph
R
(1S)
(1R)
*
*
Me
Ph NH
Ph
*
*1
2
Ph NH
Ph
*
*1
2
Ph NH
Ph
*
*1
2
(2R)
(2S)
(2S)
(1S, 2R)
(1S, 2S)
(1R, 2R)
(1R, 2S)
(2R)
Figure 3.3: Formation of enantiomeric pairs of two diastereomers assuming attack of R• at
the α-position.
Absence of any sterical hindrance for the cyclopentenyl and cyclohexenyl radicals allows
addition with the same probability from the re- and si-side affording the two diastereomers
in the ratio of 1:1.
However, in the case of α-pinene, since the si-side of the allyl radical is sterically hindered,
addition occurs preferentially from the re-side of the molecule (Figure 3.4). The HPLC-
analysis of the reaction reveals this selectivity with the observed ratio of 3:2.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
96
HN
H
Ph
Ph
re
si
Figure 3.4: Attack of α-amino cinnamyl radical at the α-pinenyl radical.
Addition Product Retention
Time [min]
Peak Area
[x 106]
Ratio of Peak Areas (diastereomer 1/ diastereomer 2)
38.0 9 7a diastereomer 1
diastereomer 2 40.5 10 1:1
49.3 12 7b diastereomer 1
diastereomer 2 52.3 13 1:1
47.2 35 7c diastereomer 1
diastereomer 2 49.4 23 3:2
Table 3.1: HPLC-Analysis data for 7a, 7b and 7c.
3.1.1.2. Mass Spectroscopy
FD-mass spectra of each isolated product show the molecular ion peak of the addition
product as the base peak. [M+] peaks with 100% abundance for 7a, 7b and 7c are at m/z:
275, 290, and 344, respectively. Because of protonation of the nitrogen atom in the
molecule, [M+ + 1] and [M+ + 2] peaks are also appearing in the spectra (Figure 3.5, e.g.
7b Adduct: M+ = 290, M+ + 1 = 291, M+ + 2 = 292). The fragment peak with m/z: 208
indicates the fragmentation to a cyclohexenyl group (see Figure 3.5, [M+ - 82] = 208).
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
97
Figure 3.5: FD-MS (2 kV, m/z): 290 [M+] for 7b in CHCl3.
From this observation, one cannot conclude if C-C coupling occurred at the α-position of
the α-aminoradical. In an amine compound cleavage starts from the α-C-C bond (next to
the nitrogen atom) and the largest branch at the α-C atom fragmentizes firstly. [1] However,
as it has been illustrated below in Figure 3.6, in the case of α-addition product, the
cycloolefin fragment cleaves from α-C to give [M+ - 82] = 208 peak, and the fragmentation
from γ-addition product also leads to the same fragment since fragmentation will not be at
the double bound. Therefore the fragmentation pattern may be similar for both α- and γ-
addition products.
N
Ph
H
R
H
Ph
- R
HN
Ph H
Ph
HN
Ph H
Ph
R:Me
N
Ph
H
Ph
R
- R
(a)
(b)
_
Figure 3.6: Fragmentation patterns. (a) For α-addition product, (b) For γ-addition product.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
98
3.1.1.3. IR
IR spectra of the addition products 7a, 7b and 7c were taken in CH2Cl2 under N2. The
spectrum of 7c is presented as an example in Figure 3.7. The new bands at about
3420 cm-1, which correspond to the characteristic ν(N ─ H) vibration bands, reveal the
presence of N-H bonds in the molecule. Aliphatic and aromatic ν(C ─ H) vibrations exhibit
peaks at about 2926, 2868 and 3026 cm-1, respectively. The peaks at 1601-1503 cm-1
correspond to the absorptions of C ═ C bonds of the phenyl rings.
Similar IR bands indicate the analogous structures for all adducts (Table 3.2).
3500 3000 2500 2000 15000
50
100
T %
W avenumber cm-1
Figure 3.7: IR spectrum of 7c.
Vibration bands 7a [cm-1] 7b [cm-1] 7c [cm-1]
ν (N ─ H) 3415 3418 3420 ν (C ─ HAr) 3053 3053 3026 ν (C ─ H) 2986
2851 2986 2860
2926 2868
ν (C ═ C) 1421 1503 1601
1421 1504 1601
1503 1601
Table 3.2: Selected IR data of adducts 7a, 7b and 7c.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
99
3.1.1.4. NMR
Although mass and IR spectroscopy are helpful analysis methods, they are insufficient to
clarify if α- or γ-addition had occurred. Therefore the NMR spectra were recorded and
analyzed in detail. In the case of the diastereomeric mixture of 7a as obtained by
preparative column chromatography, a double set of peaks is observed both for 1H-NMR
and 13C-NMR spectra. However, it was possible to separate one diastereomer (7a') by
preparative HPLC (see Experimental Section 6.5.1.2), the spectrum of which is discussed
in the following.
Figure 3.8: (a) 1H-NMR spectrum of 7a' (400 MHz, in CDCl3), (b) enlarged splitting
patterns for H7 and aromatic H12, H16, H14 (see Table 3.3) protons which come in the
same region (400 MHz, in CDCl3). Signals marked as (*) correspond to the other
diastereomer.
NH1
2
3
4
5
6 7
89 11
1213
1415
16
10
17
21
2019
18
** *
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
100
Figure 3.9: COSY spectrum of 7a (400 MHz, in CDCl3).
H9 appears at 3.88-3.91 ppm (Figure 3.8) and it couples with H8 and H17 as indicated by
the corresponding cross peak in COSY spectrum (Figure 3.9). The neighboring peak due to
N-H is observed at 3.70 ppm as a sharp singlet (Figure 3.8) since it does not couple with
H9 (Figure 3.9).
The two olefinic protons H8 and H7 are the most significant for distinguishing the α- and
γ-addition product. H8 couples with H9 and H7 (Figure 3.9) to give a doublet of doublets
at 6.07-6.12 ppm (Figure 3.8). H7 couples with only H8 and appears on the spectra as a
doublet at 6.44-6.47 ppm (Figure 3.8 (b)). The coupling constant between H8 and H7 of
16 Hz suggests that a trans olefin is present (2J7,8: 10 Hz for cis). From the appearance of a
significant roof effect (see Figure 3.8), one can conclude that the double bond is located in
α-position to a phenyl group. [1] This means that the new C-C bond was formed by
coupling of the cyclopentenyl radical with the α-C atom (C9) of the α-amino radical.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
101
The chemical shifts of these two protons also point to the α-addition product since they do
not correspond to the γ-addition product as deduced by simulated 1H-NMR spectra with the
help of the ACD®-NMR predictor program. Chemical shift values are calculated according
to well known formulas considering the substituents at geminal, cis or trans positions
which change the electron density of the surroundings and therefore the chemical shift of
H7 or H8 protons, and presented in Table 3.3. The calculated values are given for H7 and
H8 protons which would have different chemical shifts in the two structures, and also for
aromatic protons H12, H16 (chemically equivalent protons, give doublet at 6.49-6.52 ppm)
and H14 (gives triplet at 6.53-6.59 ppm) which are observed together with H7 around the
same region in the spectrum.
In the case of the α-addition product, H8 has the phenyl group at the cis position whereas it
is the –N(H)R group in the case of the γ-addition product. Therefore, the chemical shift of
H8 increases by the factor if 0.36 if it is present in the α-addition product and decreases by
the factor of 1.26 if it is present in the γ-addition product. The resulting chemical shift
value for the α-addition product (6.06 ppm) fits very well to the measured value (6.07-6.12
ppm). However, the calculated chemical shift for H8 was found as 4.44 ppm which does
not fit to the measured value.
The H7 has a phenyl group at the geminal position increasing its chemical shift value by
the factor of 1.38 in the case of the α-addition product. However, in the case of the
γ-addition product the geminal substituent is the –N(H)R group which increases the
chemical shift of H7 by the factor of 0.80. As a result, the measured chemical shift value
(6.44-6.47 ppm) for H7 also fits very well to the calculated value (6.41 ppm) for the
α-addition product but not with the calculated value for γ-addition product (5.83 ppm).
The two geminal cyclopentenyl protons at C18 are diastereotopic since they are adjacent to
a stereogenic center (C17). This neighboring causes chemically non-equivalence and
therefore gives rise to two multiplets at 1.61-1.69 ppm and 1.91-1.99 ppm (Figure 3.8).
H18 and H18` couple with each other and each of them has a different coupling to vicinal
protons H19 (2H) and H17 (1H) (Figure 3.9) to give complicated multiplet due to their
existence in a cyclic system. H19 protons couple with H18 (2H) and H20 (1H), and appear
in lower field (2.21-2.35 ppm) than the H18 protons because of the adjacent double bond.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
102
Structure Calculated Chemical Shifts
(According to method of Matter, U. E.) [1] [ppm]
δ8 δ8 = 5.25 + Igem+ Icis+ Itrans
δ8 = 5.25 + (-R) + (-Aryl) + (-H) δ8 = 5.25 + 0.45 + 0.36 + 0 = 6.06
(observed δ8 = 6.07-6.12 ppm)
δ7 δ7 = 5.25 + Igem+ Icis+ Itrans
δ7 = 5.25 + (-Aryl) + (-R) + (-H) δ7 = 5.25 + 1.38 + (-0.22) + 0 = 6.41 (observed δ7 = 6.44-6.47 ppm)
δ12,16 δ12,16 = 7.26 + Io+ Im+ Ip
δ12,16 = 7.26 + (-H + -NH-CH3) + (-H) + (-H) δ12,16 = 7.26 + (0 - 0.80) + 0 + 0 = 6.46 (observed δ12,16 = 6.49-6.52 ppm)
NH
1
21
20 19
1817 1615
14
1312
11
10
98
7
65
4
32
7a δ14 δ14 = 7.26 + Io+ Im+ Ip
δ14 = 7.26 + (-H) + (-H) + (-NH-CH3) δ14 = 7.26 + 0 + 0 + (-0.68) = 6.58 (observed δ14 = 6.53-6.59 ppm)
δ8 δ8 = 5.25 + Igem+ Icis+ Itrans
δ8 = 5.25 + (-R) + (-NR2saturated) + (-H) δ8 = 5.25 + 0.45 + (-1.26) + 0 = 4.44 (not observed) N
H
1
2120 19
1817 1615
14
1312
11
10
9 8
7
65
4
32
8a
δ7 δ7 = 5.25 + Igem+ Icis+ Itrans
δ7 = 5.25 + (-NR2saturated) + (-R) + (-H) δ7 = 5.25 + 0.80 + (-0.22) + 0 = 5.83 (not observed)
Table 3.3: Calculated chemical shift values for 7a and 8a.
The proton at C17 absorbs at 3.02 ppm and couples with H18 (2H) and H9 (1H) to give a
broad peak. H20 and H21 protons give characteristic multiplets at 5.61-5.65 ppm and 5.84-
5.86 ppm, respectively. The triplet at 7.01-7.06 ppm corresponds to the aromatic protons
H15 and H13 at the meta-position of the N-phenyl ring. Aromatic protons of the other
phenyl ring are observed as a triplet for H4 at 7.07-7.10 ppm, a triplet for chemically
equivalent H3 and H5 protons at 7.14-7.18 ppm, and a doublet at 7.22-7.25 for ortho-
position H2 and H6, respectively.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
103
Figure 3.10: 13C-NMR spectrum of 7a' (400 MHz, in CDCl3).
Further evidence for the structure of an α-addition product comes from the 13C-NMR
spectra. In the case of 7a, one diastereomer (7a') was isolated and its spectrum is displayed
in Figure 3.10 to simplify the view of the spectrum. In order to make sure the exact
chemical shifts of the signals, the cross peaks were followed in HETCOR spectrum
(Figure 3.11). Especially, the exact chemical shift of indicative signals C9, C17, and C8
and for differentiating α- from γ-addition were found by following the cross peaks in
HETCOR spectrum (Figure 3.11) and they are observed at 58.5, 51.2, and 130.7 ppm,
respectively (Figure 3.10).
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
104
Appearance of C9 at 58.5 ppm proves that it is located near the nitrogen atom. This
chemical shift value of C9 fits to the value obtained by a simulated spectrum for the
α-addition product showing the C9 signal at 61.2 ppm. However, the C9 signal in the
simulated spectrum for the γ-addition product appears at 40.9 ppm which is quite different
from the measured value. C17 is also affected by this neighboring of C9 and appears at
lower field as well but does not shift as much as C9. The C17 signal was found in
simulated spectra at 52.9 ppm for the α-addition and 46.5 ppm for the γ-addition product.
The measured chemical shift value of 51.2 ppm fits again to the α-addition product.
Observation of the C8 signal at 130.7 ppm is another evidence for the α-addition product
because it is in agreement with the calculated value for the α-addition (135.1 ppm) but not
for the γ-addition product (110.6 ppm).
The other signals in the spectrum are not so significant because they are observed at the
similar chemical shifts with the calculated values both for α-addition and also the
γ-addition product. However, since all indicative signals fit to the α-addition product, it is
concluded that the C-C coupling has occurred at the α-position.
When the corresponding cross peaks are followed in the HETCOR spectrum (Figure 3.11),
the chemical shifts of the aromatic and olefinic (C21, C20, C7) signals were observed
easier than that in the 13C-NMR spectrum (Figure 3.10). The two close peaks at 130.0 ppm
correspond to C20 and C7. Since their chemical shifts are too close to each other, they can
be seen clearly in the HETCOR spectrum presented in Figure 3.11. The other olefinic
signal C21 was observed at 134.2 ppm. The signals at 26.3 ppm and 32.4 ppm correspond
to C18 and C19, respectively. The aromatic carbons are observed for C12, C16 at the
ortho-position at 113.1 ppm and C14 at the para-position of the N-substituted phenyl ring at
116.9 ppm. The ortho-position carbons of the N-substituted phenyl C13 and C15 were
observed at 129.0 ppm. The other aromatic carbons C2,C6 at 126.3 ppm, C3, C5 at
128.4 ppm and C4 at 127.4 ppm correspond to the ortho-, meta- and para-positions of the
second phenyl ring in the molecule, respectively. The signals at 137.0 ppm and at
147.7 ppm correspond to the aromatic C1 and C11 (Figure 3.10).
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
105
18`
18
18
1917
9
N-H
19179
8
8
18`
18
18
1917
9
N-H
19179
8
8
Figure 3.11: HETCOR spectra of 7a' (400 MHz, in CDCl3).
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
106
Figure 3.12: 1H-NMR spectrum of 7b (270 MHz, in CDCl3).
In the case of the diastereomeric mixture of 7b a double set of peaks is observed for both 1H-NMR (Figure 3.12) and 13C-NMR (Figure 3.13) spectra and the assignments given
above for the single diastereomer 7a'.
The multiplet at 1.55-1.65 ppm and two adjacent multiplets at 1.85-1.94 ppm correspond to
H19I/II and H18,18’I/II, respectively. H20I/II at 2.09-2.11 ppm and H17I/II at 2.58-2.61
ppm give broad peaks on the spectrum. The singlet of N-H proton (H10I/II) is located at
3.89 ppm near by triplets of H9I at 3.96-3.99 ppm and H9II at 4.02-4.04 ppm. Whereas
H21I at 5.91-5.92 ppm and H21II at 5.96-5.97 ppm are observed as multiplet because of
coupling with H20 and H22 protons, H22I at 5.71-5.74 ppm and H22II at 5.77-5.80 ppm
are observed as doublets since H22 couples only with H21 but not with H17 because of the
dihedral angle of 90° (Karplus equation, 3JHH = Jcos2ϕ - 0.28, ϕ: dihedral angle).
NH1
23
4
56 7
89 11
1213
1415
16
10
17 21
2019
18
22
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
107
H8I and H8II are observed as doublets of doublets showing a roof-effect at 6.22-6.25 ppm
and 6.27-6.30 ppm, respectively, because of coupling with H7 and H9 according to
α-addition product. H7I/II because of coupling with H8, appear at 6.61-6.68 ppm as
doublets. Aromatic protons H12,16I/II and H14I/II of the N-substituted phenyl ring are
observed at 6.70-6.71 ppm and 6.73-6.76 ppm, respectively, in the same region as H7.
Meta-position protons H13,15I/II of the N-substituted phenyl ring are observed at 7.19-
7.27 ppm in the same region as H4I/II at 7.28-7.29 ppm, H3,5I/II at 7.31-7.34 ppm and
H2,6I/II at 7.35-7.44 ppm which correspond to para-, meta- and ortho-positions of the
second phenyl ring.
Figure 3.13: 13C-NMR spectrum of 7b (400 MHz, in CDCl3).
The 13C-NMR spectrum of 7b (Figure 3.13) also indicates that α-addition has occurred.
Carbon atoms C19I/II, C18I, C20I/II, and C18II that belong to the cyclohexenyl-ring are
observed at 21.7, 24.8, 25.2, and 26.5 ppm, respectively.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
108
Observation of C17I at 40.8 ppm, C17II at 40.9 ppm, C9I at 58.9 ppm, and C9II at
59.7 ppm because of neighboring to nitrogen atom proves α-addition as it has been
explained above for the cyclopentene addition product. Aromatic carbons of the
N-substituted phenyl ring were observed at 113.0 ppm (C12,16I), 113.4 ppm (C12,16II),
116.8 ppm (C14I), 117.2 ppm (C14II), 128.5 ppm (C13,15I/II) and 147.9 ppm (C11I/II).
While C22I is observed at 126.8 ppm, C22II appears at 128.3 ppm together with C3,5I/II.
Other olefinic carbons are observed at 129.0 ppm for C21I, at 130.5 ppm for C21II, at
131.1 ppm for C7II and at 129.9 ppm for C7I together with C8I/II. Aromatic carbons of the
second phenyl ring at the ortho-positions (C2,6I/II) and para-position (C4I/II) are observed
at 126.3 and 127.2 ppm, respectively. The singlet at 137.0 ppm corresponds to C11I/II. 1H-NMR and 13C-NMR spectra of 7c are presented in Figures 3.14 and 3.15 corresponding
to the diastereomeric mixture of the addition product. In accordance with the interpretation
of the NMR spectra for cyclopentene and cyclohexene addition products, the data indicate
the presence of the α-addition product.
Protons of α-pinenyl-ring appear at 0.89 ppm for H23I/II as singlet, at 1.11 ppm for H19I
and at 1.16 ppm for H19II as multiplets, at 1.39 ppm for H24I/II as singlet, at 1.75 ppm for
H26I/II as singlet, at 2.06 ppm for H20I/II as a multiplet, at 2.20 ppm for H18I/II as a
multiplet, at 2.40 ppm for H17I/II as a broad peak, at 5.32 ppm for H21I and at 5.49 ppm
for H21II as doublets.
The N-H proton appears at 3.84 ppm as a singlet for both diastereomers near by the narrow
triplets of H9I/II at 3.85-3.98 ppm. Olefinic protons H8I at 6.07-6.16 ppm as doublets of
doublets, H8II at 6.19-6.30 ppm as doublets of doublets and H7I/II at 6.57-6.59 ppm by
showing a roof-effect around this region of the spectrum which is an evidence of the
structure for the α-addition product as it was mentioned before. Aromatic protons were
observed as multiplets at 6.64-6.72 ppm for H12,16, H14 I/II, at 7.14-7.27 ppm for H13,15,
H4 I/II and at 7.30-7.43 ppm for H3,5, H2,6 I/II.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
109
Figure 3.14: 1H-NMR spectrum of 7c (270 MHz, in CD2Cl2/CDCl3).
Observation of C17I/II at 47.3 ppm, especially C9I at 58.1 ppm and C9II at 59.0 ppm
indicates the location of added α-pinenyl group by photocatalytic reaction at the α-position
to the amino-function in the structure. The carbon atoms at the α-pinenyl ring were
observed at 20.4 ppm for C24I/II, at 22.9 ppm for C25I/II, at 26.9 ppm for C26I/II, at
27.9 ppm for C23I, at 31.4 ppm for C23II, at 40.6 ppm for C18I/II, at 42.7 ppm for C19I/II,
at 46.5 ppm for C20I/II, at 127.4 ppm for C21I/II and at 131.6 ppm for C22I/II. The
olefinic carbons C7I/II and C8I/II were observed at 130.7 and 131.3 ppm, respectively. The
carbons of the two phenyl ring were observed at 113.2 ppm for C12,16I/II, at 116.9 for
C14I/II, at 126.3 ppm for C2,6I/II, at 128.3 ppm for C3,5I/II, at 129.1 ppm for C13,15I/II,
at 130.2 for C4I/II, at 137.0 ppm for C1I/II, at 146.9 ppm for C11I and at 147.7 ppm for
C11II.
NH1
23
4
5
6 7
89 11
1213
1415
16
10
17
21
20
19
18
22
2624
2325
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
110
Figure 3.15: 13C-NMR spectrum of 7c (270 MHz, in CDCl3).
The NMR data for all addition products as explained in Section 3.1.3.4 indicate the
presence of an α-addition product. Selected NMR data are summarized in Table 3.4. The
H8 was observed as doublet of doublets in the cases of 7a' and 7c' at about 6.07-6.16 ppm
and at about 6.22-6.30 ppm in 7b'. The H7 was observed as doublet at 6.44-6.47 ppm in
7a', at 6.57-6.59 ppm in 7c', and at 6.61-6.71 ppm in 7b'. In all cases the narrow triplet at
about 3.85-3.99 ppm corresponds to the H9 and the N-H signal appears as a singlet at about
3.70-3.90 ppm. The H17 was observed at about 2.40-2.60 ppm in 7b' and 7c' whereas it
appears at 3.02 ppm in 7a'. The H18 appears at 1.61-1.69 ppm in 7a', at 1.85-1.94 ppm in
7b', and at 2.20 ppm in 7c'.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
111
The H21 was observed at 5.84-5.86 ppm as multiplet in 7a', and as a doublet at 5.32 ppm
in 7c'. Since in the case of 7b' the H21 does not couple with H17 because of the dihedral
angle of 90°, it was observed as a doublet at 5.71-5.74 ppm.
The C17 signal was observed at 40.8 ppm in 7b', at 47.3 ppm in 7b', and at 51.2 ppm in
7a'. In all cases C9 appears at 58. C7 and C8 signals were observed at about 130 ppm for
all addition products.
Selected NMR Data for 7a', 7b' and 7c'
NH
R
1
7
89
10
11
R:
1718 21
(7a')
R:
1718 21
(7b')
R:
171821
Me
(7c') 1H-NMR, δ [ppm] (CDCl3, 270 MHz)
H8 6.07-6.12 (d) 6.22-6.30 (d) 6.07-6.16 (d)
H7 6.44-6.47 (d) 6.61-6.71 (d) 6.57-6.59 (d)
H9 3.88-3.91 (t) 3.96-3.99 (t) 3.85-3.98 (t)
H10 (N-H) 3.70 (s) 3.89 (s) 3.84 (s)
H17 3.02 (br) 2.58-2.61 (br) 2.40 (br)
H18 1.61-1.69 (m) 1.85-1.94 (m) 2.20 (m)
H21 5.84-5.86 (m) 5.71-5.74 (d) 5.32 (d) 13C-NMR, δ [ppm] (CDCl3, 270 MHz)
C17 51.2 40.8 47.3
C9 58.5 58.9 58.1
C7 130.0 129.9 130.7
C8 130.7 129.9 131.3
Table 3.4: Selected NMR Data for 7a', 7b' and 7c'.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
112
Ph NH
Ph
Ph NH
Ph
Ph NH
Ph
1.50
1.34
1.491.47
1.46
1.49
1.49
1.34
1.46
1.46
(a)
(b)
(c)
α-amino vinyl radical
γ-amino benzyl radical
Figure 3.16: Comparison of radical stabilities for two possible radical. Bond lengths were
estimated with the help of Chem3D® program.
To understand the preferential attack of the allyl radical on the α-amino allyl radical, it is
reasonable to assume that the former act as the electrophile. Since the charge density in the
(Figure 3.16 (b)) is larger at the α-position (Figure 3.16, (a)) than at the γ-position
(Figure 3.16, (c)), attack at the former should be favored. In addition, sterical hindrance at
the γ-position may also direct the attack to the α-position.
3.1.2. Thermodynamic Aspects
The photogenerated electrons and holes in a semiconductor can be thought as reducing and
oxidizing surface centers, respectively. If the reduction potential level of the imine
(electron acceptor) lies below the conduction band edge and the oxidation potential of the
olefin (electron donor) locates at a higher potential level than the valence band edge of the
semiconductor, thermodynamic feasibility is fulfilled for the interfacial electron transfer.
Therefore, thermodynamic feasibility of the addition between olefins and 6 can be clarified
by the comparison of band edge positions of the photocatalyst with redox potentials of the
substrates.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
113
The reduction potential of 6 was determined by cyclic voltammetry measurement in
MeOH. From the first reversible wave in the cathodic region, the first reduction potential of
6 was found as -0.35 V (Figure 3.17). Band edge positions of CdS were determined in H2O
(at pH:7) by photovoltage measurements (see Chapter 2.3.2) and estimated for that in
MeOH according to the reference [2]. Location of band edge positions of CdS/Al2O3 and
redox potentials of 6 and olefins are illustrated in Figure 3.18. From this comparison, since
redox potentials of the substrates locate between the band edges of the semiconductor,
IFET from olefinic substrates and to the imine substrate seems thermodynamically favored.
-800 -400 0 400
-0,003
-0,002
-0,001
0,000
0,001
E [mV]
I [µA
]
-138.9
-564.2
E: -0.35 V
Figure 3.17: Cyclic voltammogram of 6 in MeOH; potential values are relative to NHE
(pH= 7).
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
114
2
1
0
-1
R + H+ / RH
hν
in H2O in MeOH
6-0.39
+2.01+
-0.69
+1.71
-0.35
V [NHE]
Figure 3.18: Location of band edge positions of 30% CdS/Al2O3(n) and potentials for
imine reduction and olefin oxidation.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
115
3.2. Photocatalytic Addition Reactions with N-(1-Adamantyl)-p-X-
benzaldehyde Imine (X: -H, -F, -Cl, -Br, -OCH3)
3.2.1. Photocatalytic addition reactions of N-(1-adamantyl)-p-chloro-
benzaldehyde imine with cyclopentene, cyclohexene, and α-pinene.
The photocatalytic addition reactions of cyclopentene, cyclohexene, and α-pinene were
firstly performed with the p-chloro-substituted derivative of N-(1-adamantyl)-benzaldehyde
imine (Figure 3.19). Subsequently, p-fluoro, p-bromo, p-methoxy substituted and
unsubtituted derivatives of the imine substrate were also synthesized and two series of
addition reactions with cyclohexene (see Section 3.2.2) and α-pinene (see Section 3.2.3)
were carried out in order to investigate the influence of p-substitution.
+ R-H
30%CdS/Al2O3 hν
MeOH/CH2Cl2
Ad:
Ar: Cl
R:Me
a b c
N
Ad Ar
HHN
Ad Ar
H
R +HN
Ad Ar
HN
Ad Ar
11 16a-c 20-20'
yield 21-62%
Figure 3.19: CdS-photocatalyzed addition of olefins to N-(1-adamantyl)-p-chloro-
benzaldehyde imine.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
116
All reactions were carried out under N2 atmosphere in a Pyrex immersion lamp apparatus
(see Experimental Section 6.1.1, Figure 6.1) and a 100W tungsten halogen lamp was used
as the irradiation source. The reason for using CH2Cl2/MeOH mixture as solvent is the poor
solubility of the imine substances in MeOH. Reaction progress was followed by HPLC and
TLC analysis. After complete consumption of the imine, irradiation was stopped, the
catalyst was filtered off and the solvent was removed under reduced pressure. The product
mixtures were obtained as yellow oils in every case. Purification by preparative column
chromatography packed with silica provided addition products as light yellow oils in the
yields of 21-62% and hydrodimers as white powders. Crystallization afforded colorless
crystals.
3.2.1.1. HPLC Analysis
HPLC chromatograms for addition products and hydrodimers are presented in Figure 3.20
and corresponding data are listed in Table 3.5.
As discussed in the previous chapter, the addition product is observed as two diastereomers
which consist of enantiomeric pairs. However, in the HPLC chromatograms only in the
case of cyclohexene addition the peaks were clearly separated and it was possible to
determine diastereomeric ratio and retention times of the two diastereomers (Table 3.5).
HPLC analysis of the reaction solution exhibited one hydrodimer peak (20) at retention
time of 22 min in the case of cyclopentene and α-pinene addition. Surprisingly, the HD
isolated from the cyclohexene addition exhibited a peak at 31 min (20′). According to
X-ray structural analysis 20 and 20′ are two diastereomers (Figure 3.24). Upon dissolution
of each of the two crystalline diastereomers and HPLC analysis, it turns out that the peaks
exactly correspond to the peaks obtained from the reacting solution (Figure 3.20). From
these observations, one must conclude that hydrodimer formation is diastereoselective
affording one identical diastereomer (20) in the case of cyclopentene and α-pinene
addition, and the other diastereomer (20′) in the case of cyclohexene addition.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
117
Figure 3.20: HPLC-Analysis of reaction solution (a) and isolated diastereomers 20 and 20'
of hydrodimer of 11 (b) (detection at 230 nm, eluent: CH3CN/CH2Cl2= 90/10 (v/v), for the
instrumental set-up of the HPLC see Experimental Section 6.1.3.12).
HPLC Chromatograms
(a)
20 16a
16b 20′
20 16c
Cyclopentene addition Cyclohexene addition α-Pinene addition
(b)
20 20′
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
118
HPLC Data for Addition Products and Hydrodimers
Addition Product [16a-c]
Hydrodimer [20, 20′]
Olefin tR [min] diast1; diast2
diastereomeric ratio
diast1/diast2 tR [min] ratio
16 / 20
Cyclopentene 23.9 - 22.1 1:4
Cyclohexene 16.9; 18.6 5:3 31.4 2:1
α-pinene 24.3 - 21.9 9:5
Table 3.5: HPLC-Data for CdS-photocatalzed addition reaction of olefins to 11 (detection
at 230 nm, eluent: CH3CN/CH2Cl2= 90/10 (v/v)).
3.2.1.2. Mass Spectroscopy
The base peak of aliphatic amine compounds, frequently results from α-C-C cleavage and
the molecular ion peak is usually quite weak or undetectable. [3] Therefore, in the mass
spectra of the addition and hydrodimer products, the molecular ion peak is very weak. The
base peak of m/z = 275 corresponds to the fragment formed by cleavage of cyclopentenyl-,
cyclohexenyl- and α-pinenyl- branch of 16a, 16b and 16c, respectively.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
119
Cyclopentene addition product (16a) / m/z = 343
Cyclohexene addition product (16b) / m/z = 357
α-Pinene addition product (16c) / m/z = 410
Hydrodimer (20) / m/z = 550
Figure 3.21: Mass spectra of 16a-c and hydrodimer products, (FD-MS, in CH2Cl2).
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
120
3.2.1.3. Structure Determination by NMR and X-Ray
All NMR spectra correspond to a diastereomeric mixture of the addition products. The
structure of each diastereomer for cyclopentene and cyclohexene addition products were
solved by crystal structure analysis. According to crystallographic data, the addition
products are present as two diastereomers and each diastereomer also consists of two
enantiomeric pairs.
Figure 3.22: 1H-NMR spectrum of 16a (270 MHz, in CDCl3).
Because of the diastereomeric mixture, the aromatic protons of 16a appear at 7.03-7.30
ppm and H19 at 5.70-5.73 ppm as double signals. The diastereotopic H22 protons of the
cyclopentenyl ring were observed at 1.21-1.36 ppm as two adjacent multiplets.
1516
17
1213
1411
18 22
2
6
21
10
9
4
20
58
19
1
7
3
NH
CH
Cl
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
121
Protons of adamantyl-ring appear as large multiplet for H2,6,7,10,4,9 at 1.37-1.54 ppm and
as a multiplet at 1.80-1.93 ppm for H8,3,H5.
The protons of the cyclopentenyl ring were observed at 2.25-2.26 ppm, 2.82 ppm, and
5.22-5.25 ppm, respectively. The N-H proton gives a sharp singlet at 3.65 ppm because the
vicinal coupling 3J(CH-NH) is not observed due to rapid proton exchange. H11 was
observed as a doublet at 3.74 ppm because of coupling with H18.
Selected NMR data for 16a-c are presented in Table 3.6.
Selected NMR Data for 16a, 16b and 16c
1516
17
1213
1411
2
610
9
4
58
1
7
3
NH
CH
Cl
RR:
1819
21
22
20
(16a)
R:
19
212220
1823
(16b)
R:
27
19
21
22
20 26
23
25
18
24Me
(16c) 1H-NMR, δ [ppm] (CDCl3, 270 MHz)
H11 3.74 (d) 4.12 (br) 3.73 (s)
H18 2.82 (m) 2.19-2.29 (m) 3.61-3.64 (d)
H19 5.70-5.73 (m) 5.72-5.73 (m) 5.32-5.49 (d)
H20 5.22-5.25 (m) 5.68-5.69 (m) -
N-H 3.65 (s) 4.12 (br) 4.41 (br)
H21 2.25-2.26 (m) 1.78-1.81 (m) 3.67-3.69 (d) 13C-NMR, δ [ppm] (CDCl3, 270 MHz)
C1 41.6 39.9 43.4
C11 53.4 64.0 58.4
C18 51.9 46.0 I, 54.8 II 43.8
C19 128.7 128.6 128.0
C20 128.3 126.7 129.7
Table 3.6: Selected NMR data for 16a-c.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
122
In the case of 16a the H11 proton appears as a doublet at 3.74 ppm, whereas in 16c a
chemical shift of 3.73 ppm is found. The H11 signal of 16c was observed as a singlet
instead of a doublet because it does not couple with H18. The H18 proton couples only
with H19 and appears as a doublet for each diastereomer (see also Chapter 3.2.3, Table
3.11). In the case of 16b, H11 and N-H protons were observed together at 4.12 ppm. The
N-H peak of 16c is a broad signal at 4.41 ppm. For 16a the N-H signal is found at 3.65
ppm.
Crystallization of 16a in CH3CN gave colorless crystals which were subjected to crystal
structure analysis. According to the crystallographic data, 16a forms monoclinic crystals
and the cyclopentene ring is disordered indicating the existence of two diastereomers of
16a within the crystal (Figures 3.23 and 3.24). In addition, the two diastereomers are
present as enantiomeric pairs (Figure 3.31). Fortunately, the different crystals of the two
diastereomers could be separated due to their different crystal form. In Figure 3.29 the
crystal structure of the diastereomers are depicted.
Figure 3.23: Superposition of two diastereomers of 16a.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
123
Figure 3.24: Crystal structure of two diastereomers of 16a.
Diastereomer 1
Diastereomer 2
R
S
S
S
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
124
H
NHAdAr *
*
S
S
S
S R
R
R
R
H
ArAdHN *
*
H
ArAdHN *
*
H
NHAdAr *
*
Ad: Ar: Cl
Diastereomer1
Diastereomer2
Enantiomer1 ofDiastereomer1
Enantiomer2 ofDiastereomer1
Enantiomer1 ofDiastereomer2
Enantiomer2 ofDiastereomer2
Figure 3.25: Cyclopentene adduct 16a existing as enantiomeric pairs of two diastereomers.
The cyclohexene addition product crystallized from CHCl3/n-hexan/(CH3)3CCN giving
colourless monoclinic crystals. Similar to the cyclopentene adduct, two diastereomers
consisting of the enantiomeric pairs of (RS, SR) and (SS, RR) diastereomers (Figure 3.26)
are formed.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
125
Figure 3.26: Crystal structure for two diastereomers of 16b.
Diastereomer 1
Diastereomer 2
S
S
S
R
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
126
Figure 3.27: Superposition of the disordered parts of the structure 16b.
Structures of hydrodimers were also identified by NMR spectroscopy and X-ray crystal
structure analysis.
Figure 3.28: 1H-NMR spectrum of hydrodimer 20 (270 MHz, in CDCl3).
NH HN
ClCl
5
6
3
2
11
10
87
4
1 1213
149
1615
17 18
252419
2620
2122
23
2728
29
35
3433
36
30
3132
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
127
In the 1H-NMR spectrum of hydrodimer 20, the protons of adamantyl rings are observed of
0-87-1.99 ppm (Figure 3.28). The large multiplet includes H18,28, H24,34 (doublet) and
H22,32,20,30,25,35,26,36 (triplet). However, since their chemical sifts are in the same
region (0.87-1.64), they can not be observed separately. A broad peak at 1.89-1.99 ppm
corresponds to H33,29,31,23,19,21 of the adamantyl rings. Two sharp singlets at 3.68 ppm
and 3.81 ppm arise from N-H and H7,8 protons of the hydrodimer, respectively. Aromatic
protons were observed at 7.03-7.34 ppm.
Figure 3.29: 13C-NMR spectrum of hydrodimer 20 (270 MHz, in CDCl3).
The 13C-NMR spectrum of hydrodimer 20 is presented in Figure 3.29. The
C19,21,23,29,31,33 carbon atoms of two adamantyl rings appear all together at 29.5 ppm.
Other carbons that belong to adamantyl rings were observed at 36.5 ppm for
C20,22,26,30,32,36, at 43.8 ppm for C18,24,25,28,34,35 and at 51.0 ppm for C17 and C27
that are in α-position to nitrogen.
The signals at 60.8 ppm and 61.4 ppm correspond to C7 and C8, respectively. Aromatic
carbons were observed at 127.7 ppm for C2,6, 127.8 ppm for C11,13, 128.9 ppm for C3,5,
129.6 ppm for C10,14, 131.6 ppm for C1, 132.3 ppm for C12, 143.6 ppm for C4 and 144.4
ppm for C9.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
128
20′
20
Figure 3.30: Crystal structure for hydrodimer of 11. Structure 20′ indicates product from
cyclohexene addition, structure 20 was obtained from cyclopentene or α-pinene addition
reaction.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
129
1H and 13C NMR spectra examples and interpretations have been depicted in Section 3.2.2
for cyclohexene, in Section 3.2.3 for α-pinene addition products with various substituted
and unsubstituted imine derivatives.
3.2.2. Photocatalytic Addition Reactions of N-(1-Adamantyl)-p-X-
benzaldehyde Imine (X: -H, -F, -Cl, -Br, -OCH3) with Cyclohexene
Photocatalytic addition of cyclohexene was performed with unsubstituted, chloro-, fluoro-,
bromo- and methoxy-substituted derivatives of N-(1-adamantyl)-benzaldehyde imine in
satisfactory to good yields (47-82%). The yields given in Figure 3.31 correspond to
isolated diastereomeric mixture of addition products after column chromatography.
The hydrodimer of the imine was isolated only for the p-chloro derivative in order to
determine its molecular structure. For the bromo-substituted imine, the hydrodimer of 12
could be detected by HPLC but was not isolated since the ratio of addition product /
hydrodimer is very high (ratio: 13:1, see Table 3.7). In the other cases no hydrodimer was
detectable by HPLC analysis.
+30%CdS/Al2O3 hνMeOH/CH2Cl2
Ad:
Ar: X
NAd Ar
HHN
Ad ArH +
HNAd Ar
HNAd Ar
9-13 b 14-18b 20,21
X -H -F -Cl -Br -OCH3 9 10 11 12 13
Addition 14b 15b 16b 17b 18bProduct
Hydrodimer - - 20 21 -
Yield % 59 82 62 79 47
Figure 3.31: CdS-photocatalyzed addition of cyclohexene to unsubstituted and substituted
N-(1-adamantyl)-benzaldehyde imine derivatives.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
130
HPLC data are presented in Table 3.7.
HPLC Data for Cyclohexene Addition Reactions
Addition Product (AD) [14-18b]
Hydrodimer (HD) [20,21]
Ad-N=C(H)C6H4X tR [min]
diast1-diast2
diastereomeric ratio
diast1/diast2 tR [min] ratio
AD/ HD
X: -Cl 16.9 -18.6 5:3 31.4 2:1
X: -F 13.2 – 14.3 9:4 - -
X: -Br 17.3 – 19.0 6:5 41.4 13:1
X: -OCH3 14.8 - - -
X: -H 15.3 – 16.4 1:1 - -
Table 3.7: HPLC-Data for CdS-photocatalzed reaction of cyclohexene with 9-13,
(detection at 230 nm, eluent: CH3CN/CH2Cl2=90/10 (v/v)).
Listed diastereomeric ratios were determined from the HPLC peak areas. However, only in
the case of p-methoxy derivative such determination could not be achieved since the peaks
of two diastereomers could not be separated.
According to HPLC data only in the case of unsubstituted imine derivative the ratio of two
diastereomers was 1:1. For other derivatives one of diastereomers was observed in a higher
concentration. Therefore, one can conclude that the electrophilic attack of the cyclohexenyl
radical occurs preferentially at one side of the α-amino aryl radical.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
131
Figure 3.32: 1H-NMR spectrum of 17b (270 MHz, CDCl3).
The 1H NMR spectrum of 17b is depicted in Figure 3.32 as an example of a cyclohexene
addition product. The region of 0.7-2.0 ppm corresponds to adamantyl ring protons and
H18, H21, H23, H22 of the cyclohexenyl ring. N-H and H11 protons were observed
together as a broad peak at 4.12 ppm for all cyclohexene addition products except in the
case of the p-fluoro-phenyl derivative, which exhibits a singlet for N-H and a doublet for
H11, separately. Olefinic H19 and H20 give two multiplets for all cyclohexene adducts at
around 5.60-5.98 ppm. This differs from the other addition product of olefins and imines in
which case the two signals were separated by 0.1 to 0.3 ppm.
Corresponding 1H NMR data for all cyclohexene addition products have been listed in
Table 3.8.
1516
17
1213
1411
18 23
2
6
22
10
9
4
21
58
20
19
7
3
NH
CH
Br
1
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
132
X: -H, -F, -Cl, -Br, -OCH3
1516
17
1213
1411
18 23
2
6
22
10
9
4
21
58
20
19
7
3
NH
CH
X
1
1H-NMR Data for
δ [ppm]
proton -H 14b
-F 15b
-Cl 16b
-Br 17b
-OCH3 18b
H11 4.13 (br)
3.77-3.85 (d)
4.12 (br)
4.14 (br)
4.45 (br)
H18 2.53 (m)
2.13-2.14 (m)
2.19-2.29 (m)
1.75-1.79 (m)
2.03-2.04 (m)
H19 5.93-5.98 (m)
5.73-5.76 (m)
5.72-5.73 (m)
5.61-5.79 (m)
5.89-5.94 (m)
H20 5.66-5.72 (m)
5.65-5.69 (m)
5.68-5.69 (m)
5.61-5.79 (m)
5.68-5.69 (m)
H21 2.27-2.38 (m)
1.64-1.82 (m)
1.78-1.81 (m)
1.23 (m)
1.89-1.98 (m)
H22 1.15 (m)
0.81-0.82 (m)
1.16-1.18 (m)
0.77-0.79 (m)
0.75-0.83 (m)
H23 1.18-1.24 (m)
0.96-1.00 (m)
1.29-1.34 (m)
1.08 (br)
1.14-1.22 (m)
N-H 4.13
4.12 4.12 4.14 4.45
H2,6,7 1.78-2.02 (m)
1.39-1.53 (m)
1.59-1.63 (m)
1.39-1.42 (m)
1.63-1.69 (m)
H8,5,3 2.27-2.38 (m)
1.89 (br)
1.85-1.94 (m)
1.80-1.90 (m)
1.89-1.98 (m)
H10,4,9 1.41-1.76 (m)
1.39-1.53 (m)
1.41-1.56 (m)
1.42-1.54 (m)
1.63-1.69 (m)
Haromatic 7.12-7.32
6.85-7.26 7.14-7.25 7.17-7.38 7.20-7.26
Table 3.8: 1H-NMR data for cyclohexene addition products.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
133
Figure 3.33: 13C-NMR spectrum of 15b (270 MHz, CDCl3).
The 13C-NMR spectrum of 15b is given in Figure 3.33 as an example for cyclohexene
addition products and 13C-NMR data summarized in Table 3.9. The C11 carbon signal for
unsubstituted, p-bromo, and p-chloro derivatives appear at about 65 ppm but for methoxy-
and fluoro-substituted derivatives at 76.5 ppm and 51.2 ppm, respectively. C18 signals
were observed at about 45 ppm for p-chloro and unsubstituted, at around 35 ppm for
p-bromo and p-methoxy and at 53 ppm for fluoro-substituted derivative. The C19 signals
appeares at 129 ppm except for p-methoxy derivative (133.8 ppm). The other olefinic
carbon C20 was observed at 125-127 ppm except for fluoro-phenyl derivative (114.9 ppm).
1516
17
1213
1411
18 23
2
6
22
10
9
4
21
58
20
19
7
3
NH
CH
F
1
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
134
X: -H, -F, -Cl, -Br, -OCH3
1516
17
1213
1411
18 23
2
6
22
10
9
4
21
58
20
19
7
3
NH
CH
X
1
13C-NMR Data for
δ [ppm]
carbon -H 14b
-F 15b
-Cl 16b
-Br 17b
-OCH3 18b
C15 127.3 142.9 128.8 129.4 140.7
C16,14 127.6 114.5 126.2 130.5 123.9
C17,13 129.9 128.5 127.8 129.8 133.9
C12 150.6 129.0 129.5 131.2 133.9
C11 65.1 51.2 64.0 65.4 76.5
C18 44.3 52.8 46.0 36.6 34.1
C19 129.6 128.6 128.6 129.8 133.8
C20 127.5 114.9 126.7 128.2 124.4
C21 29.8 29.5 35.4 29.5 22.2
C22 18.8 20.6 19.4 14.1 14.0
C23 24.8 23.4 28.2 18.6 18.3
C1 35.0 43.3 39.9 35.5 25.3
C2,6,7 37.8 43.9 30.9 31.9 26.8
C8,5,3 22.4 29.5 17.8 18.9 18.2
C10,4,9 26.8 36.5 23.8 24.9 25.3
Table 3.9: 13C-NMR data for cyclohexene addition products.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
135
3.2.3. Photocatalytic Addition Reactions of N-(1-Adamantyl)-p-X-
benzaldehyde Imine (X: -H, -F, -Cl, -Br, -OCH3) with α-Pinene
The photocatalytic addition of α-pinene was performed with unsubstituted, chloro-, fluoro-,
bromo- and methoxy-substituted derivatives of N-(1-adamantyl)-benzaldehyde imine in
satisfactory to good yields (21-85%). The given yields in Figure 3.34 correspond to
isolated diastereomeric mixture of addition products after column chromatography.
Hydrodimers of imines were only detected by HPLC but not isolated except the
hydrodimer of 11. The unsubstituted phenyl derivative afforded only the addition product.
Ad:
Ar: X
X -H -F -Cl -Br -OCH3 9 10 11 12 13
Addition 14c 15c 16c 17c 18cProduct
Hydrodimer - 19 20 21 22
Yield % 71 81 21 85 61
+
30%CdS/Al2O3 hν
MeOH/CH2Cl2N
Ad Ar
HHN
Ad Ar
H +HN
Ad Ar
HN
Ad Ar
9-13 c 14-18c 19-22
Me
Figure 3.34: CdS-photocatalyzed addition of α-pinene to N-(1-adamantyl)-benzaldehyde
imine derivatives.
HPLC data are presented in Table 3.10.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
136
HPLC Data for α–Pinene Addition Reactions
Addition Product (AD)
[14-18c] Hydrodimer (HD)
[19-22] Ad-N=C(H)C6H4X tR [min]
diast1-diast2
diastereomeric ratio
diast1/diast2 tR [min] ratio
AD / HD
X: -Cl 24.3 - 21.9 9:5
X: -F 22.1 – 23.4 5:3 19.8 4:5
X: -Br 25.6 - 22.2 2:1
X: -OCH3 22.3 - 18.9 1:2
X: -H 21.9 - - (a)
Table 3.10: HPLC-Data for CdS-photocatalzed addition reaction of α-pinene to 9-13,
(detection at 230 nm, eluent: CH3CN/CH2Cl2=90/10 (v/v)). (a) No hydrodimer was
detectable.
A diastereomeric ratio of 5:3 was determined from HPLC peak areas only for the p-fluoro
phenyl derivative since the peaks of two diastereomers for other derivatives could not be
separated with the used eluent system.
All imines afforded also the hydrodimer product except for the phenyl derivative, as it has
been noted for cyclohexene addition as well. The ratio of addition/hydrodimer was found
higher for chloro-, fluoro- and bromo- substituted derivatives, whereas it decreased to 0.5
for the p-methoxy substituted one. However, none of these hydrodimers was isolated in this
work.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
137
Figure 3.35: 1H-NMR spectrum of 14c (270 MHz, CDCl3).
The 1H-NMR spectrum of 14c is presented in Figure 3.35 as an example for α-pinene
addition products. H25 and H26 methyl protons of the α-pinenyl ring are observed as
singlets at 1.61 ppm and 0.72 ppm, respectively. However, the singlet of methyl group H27
appears together with the multiplet of H4,9,10 protons of the adamantyl ring at around
1.16-1.25 ppm. The H24 diastereotopic protons of the α-pinenyl ring appear as two
adjacent multiplets at 0.85-0.96 ppm. Whereas H3,5,8 protons of the adamantyl ring give
rise to a multiplet at 1.01-1.13 ppm, a broad signal at about 1.45 ppm was observed for
H2,6,7. The H21 and H23 protons of the α-pinenyl ring appear as two broad peaks at 1.84-
1.87 ppm and at 2.06-2.11 ppm, respectively.
Observation of the H18 as a doublet at 3.54-3.57 ppm for one of two diastereomers and at
3.63-3.66 ppm for the other, because of coupling with only H19, also indicates that H18
and H23 do not couple with each other. In addition, because of the coupling of H18 only
with H19, H11 was observed as singlet at 3.73 ppm.
1516
17
1213
1411
18 19
2
6
20
10
9
4
25
58
21
24
7
3
NH
CH1
23
22
26
27
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
138
The olefinic H19 proton gives two doublets because of diastereomeric mixture of the
addition product at around 5.04-5.21 ppm. For all α-pinene addition products, the N-H
proton was observed as a broad peak at 4.40 ppm. The multiplet around 7.08-7.31 ppm
corresponds to aromatic protons of 14c. 1H-NMR data for all α-pinene addition products are given in Table 3.11.
Figure 3.36: 13C-NMR spectrum of 17c (270 MHz, CDCl3).
The 13C-NMR spectrum of 17c is given in Figure 3.36 as an example; for all other spectra
see Table 3.12. Apart from aromatic carbons, similar chemical shifts were observed for all
α-pinene addition products and because of diastereomeric mixture some carbon signals
(e.g. C18, C19, C20) are doubled.
1516
17
1213
1411
18 19
2
6
20
10
9
4
25
58
21
24
7
3
NH
CH
Br
1
23
22
26
27
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
139
1H-NMR Data for X: -H, -F, -Cl, -Br, -OCH3
1516
17
1213
1411
18 19
2
6
20
10
9
4
25
58
21
24
7
3
NH
CH
X
1
23
22
26
27
δ [ppm]
proton -H 9c
-F 10c
-Cl 11c
-Br 12c
-OCH3 13c
H26 0.72 (s) 0.71 (s) 0.92 (s) 0.78 (s) 0.71 (s) H24
0.85-0.96 (m)
0.84-0.92 (m)
1.08-1.10 (m)
0.90-0.97 (m)
0.89-0.92 (m)
H3,5,8 1.01-1.13 (m)
1.04-1.10 (m)
1.12-1.17 (m)
1.08-1.18 (m)
1.04-1.09 (m)
H4,9,10 (m) H27 (s)
1.16-1.25
1.15-1.26 1.20-1.27
1.22-1.30
1.16-1.27
H2,6,7
1.45 (br)
1.46-1.47 (br)
1.47-1.52 (br)
1.49-1.53 (br)
1.47 (br)
H25 1.61 (s) 1.60 (s) 1.67 (s) 1.65 (s) 1.59 (s) H21 1.84-1.87
(br) 1.84-1.87 (br)
2.06-2.14 (br)
1.92-1.98 (br)
1.84-1.92 (br)
H23 2.06-2.11 (br)
2.06-2.11 (br)
2.17-2.34 (br)
2.08-2.14 (br)
2.05-2.08 (br)
H18I 3.54-3.57 (d)
3.56-3.62 (d)
3.61-3.64 (d)
3.60-3.77 (d)
3.59-3.66 (d)
H18II 3.63-3.66 (d)
3.65-3.71 (d)
3.67-3.69 (d)
3.60-3.77 (d)
3.59-3.66 (d)
H11 3.73 (s) 3.76 (s) 3.73 (s) 3.77 (s) 3.71 (s) N-H 4.37 (br) 4.36 (br) 4.41 (br) 4.42 (br) 4.39 (br) H19I/II
5.04-5.21 (d)
5.14-5.31 (d)
5.32-5.49 (d)
5.20-5.44 (d)
5.14-5.32 (d)
Haromatic 7.08-7.31 6.84-7.21 7.04-7.28 7.08-7.36 6.70-7.21
Table 3.11: 1H-NMR data for α-pinene addition products.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
140
13C-NMR Data for X: -H, -F, -Cl, -Br, -OCH3
1516
17
1213
1411
18 19
2
6
20
10
9
4
25
58
21
24
7
3
NH
CH
X
1
23
22
26
27
δ [ppm]
carbon -H 9c
-F 10c
-Cl 11c
-Br 12c
-OCH3 13c
C25 20.4 20.3 21.7 20.3 20.3 C26,27 23.1 23.0 25.2 23.1 23.0 C3 26.4 26.5 29.4 26.5 26.3 C5,8 27.6 27.6 29.5 27.6 27.7 C4,9,10 29.6 29.6 36.5 29.5 29.9 C24 29.4 29.4 36.4 29.7 29.3 C22 36.6 36.6 38.6 36.4I-36.6II 36.5 C2,6,7 40.5 40.4 43.6 40.5 40.4 C1 41.0 41.0 43.4 41.0 40.9 C18I 42.4 42.4 43.8 42.8 42.7 C18II 43.0 43.1 43.8 43.1 43.0 C23 44.1 43.8 43.8 43.7I-43.9II 43.9 C21 47.4 47.4 51.3 47.1 47.3 C11 58.2 57.5 58.4 60.7 54.9 C19I 118.5 118.5 128.0 118.5 118.4 C19II 119,1 118.8 128.0 118.9 118.4 C15 119.6 163.1 131.5 119.6 157.8 20I 127.7 128.5 129.7 129.2 128.1 20II 127.7 129.6 129.7 129.6 131.8 13,17 127.2 128.9 129.1 130.0 128.5 14,16 127.8 119.6 128.2 130.7 113.1 12 144.2 144.2 132.4 144.4 144.2
Table 3.12: 13C-NMR data for α-pinene addition products.
Chapter 3. CdS-Photocatalyzed Synthesis of Homoallylamines
141
References:
[1] M. Hesse, H. Meier, B. Zeeh, Spektroskopische Methoden in der Organischen
Chemie, 3. überarbeitete Auflage, Georg Thieme Verlag Stuttgart, New York, 1987.
[2] G. Redmond, D. Fitzmaurice, J. Phys. Chem. 1993, 97, 1426.
[3] R. M. Silverstein, G. C. Bassler, Spectrometric Identification of Organic
Compounds, Second Ed., John Willey & Sons, Inc., New York, 1967.
Chapter 4. Summary 142
CHAPTER 4 4. Summary The aim of this work was to investigate the general applicability of the recently reported
CdS catalyzed photoaddition of cyclic olefins to imines. Furthermore, it should be
investigated if the rate accelerating effect of the covalent attachment of CdS onto silica
(SEMSI effect), as previously published, can be extended to various alumina supports.
C NH
Ar
Ar
MeOHC N
H
HAr
ArCH
CHAr NHAr
Ar NHAr+
CdS/hν+
In the first part of the work, the electronic semiconductor-support interaction (SEMSI)
effect was investigated for alumina supported CdS powders. In the case of alumina
supported CdS, very slight band-gap widening (0.02-0.06 eV) and band-edge shift have
been observed (Figure 4.1). The relatively larger band-gap shifts correspond to acidic
alumina supported photocatalysts (30AII and 10AII) and the neutral alumina supported
catalyst prepared in more basic impregnation solution (30NII25). From XRD analyses and
high resolution transmission electron micrographs, the cubic structure of CdS powders was
identified without ambiguity with a crystal size of 8-20 nm.
Since it is known in the literature that the method employed for quasi-Fermi level
measurements is light intensity dependent, corresponding experiments were conducted. It
turned out that under given experimental conditions the obtained values did not depend on
light intensity. In addition, it was found that the absence or presence of a reducing agent
(4.1)
Chapter 4. Summary 143
has no significant effect. This suggests that the photoproduced holes oxidized lattice sulfide
to elemental sulfur as evidenced by XPS analysis.
CdS-A 10NII 30NII25 30BII 30AII 10AII
2,5
2,0
1,5
1,0
0,5
0,0
-0,5 ⎯ ⎯ ⎯ ⎯ ⎯ ⎯
⎯ ⎯ ⎯ ⎯ ⎯ ⎯
2.462.432.412.482.452.39
+ 2.07+ 2.06+ 2.04+ 1.97 + 2.10+ 2.10
- 0.36- 0.36- 0.35- 0.38- 0.41- 0.42
Photocatalysts
E(F
B)[V
]
Figure 4.1: Band edge positions (+ 0.02 V) and band-gap energies (+ 0.01 eV) for CdS
photocatalysts at pH=7.
Since band edges do not shift significantly, and the valence and conduction bands have
sulfur and cadmium character, respectively, binding energies differ only very little (0.4 eV)
for both Cd3d and S2p electrons as determined by X-ray photoelectron spectroscopy.
Measurement of the time resolved photovoltage shows that the lifetime of the
photogenerated surface charges increases from 0.76 µs to 1.20 µs when CdS is supported
onto neutral alumina (see Table 4.1). This parallels the increase of the band-gap energy
from 2.39 to 2.45 eV. Similarly, the reaction rate of olefin addition (Eq. 4.1) is increased
approximately by a factor of 4 when the sample 10NII is used instead of unsupported CdS,
and by a factor of about 6 in the case of 30NII25 (Table 4.2).
Chapter 4. Summary 144
Photocatalysts Ebg
[eV]
Lifetime
[10-6 s]
Reaction Rate
[10-7 moll-1s-1]
CdS-A 2.39 0.76 0.24
50NII 2.42 0.75 0.25
30NII 2.43 0.86 0.36
10NII 2.45 1.20 0.84
Table 4.1: Band edge positions, band-gap energies and lifetime values of unsupported CdS
and 10-50% CdS/Al2O3(n) in comparison with reaction rates.
Photocatalysts
Ebg
[eV]
Lifetime
[10-5 s]
Reaction Rate
[10-7 moll-1s-1]
30AII 2.43 0.57 0.34
30NII 2.43 0.61 0.36
30NII25 2.48 0.64 1.97
Table 4.2: Band edge position, band-gap and lifetime values in comparison with reaction
rates of 30wt% Al2O3 supported CdS photocatalysts.
In conclusion, it was found that in the case of alumina supported CdS, the SEMSI effect is
not as strong as in the case of silica supported CdS. The reason for this fact can be
explained by the different electronegativity of Al and Si which influences electron density
on the support oxygen atom. The lower electronegativity of Al (1.47) than Si (1.74) causes
a lower change in electron density on oxygen and Cd leading to a smaller shift in band edge
positions.
Chapter 4. Summary 145
Ph NPh R-H
MeOH
Ph NH
Ph
R
Ph NH
Ph
Ph NH
PhR
hν+
30% CdS/Al2O3
addition at α-position addition at γ-position
R: Me
isolated yield% 67 72 48
Figure 4.2: Photocatalytic addition reaction between N-Cinnamylideneaniline and
cyclopentene, cyclohexene and α-pinene.
In the second part of this work, novel homoallylamine derivatives were synthesized by
semiconductor photocatalysis.
In first set of synthesis work, in order to investigate general applicability of the
photocatalytic addition reactions between imines and olefins, the known photoaddition
reaction was extended to the α,β-unsaturated imine N-Cinnamylideneaniline, which
contains the nitrogen-terminated conjugated system in an open chain.
Irradiation of 30% CdS/Al2O3(n) in a methanolic solution of N-Cinnamylideneaniline and
an excess of olefin produces corresponding novel homoallylic secondary amines, which are
C-C coupling products between the α-amino cinnamyl radical of the imine and the allylic
radical of the olefin (Figure 4.2). Structures of these new products were identified by
NMR, IR, and MS analysis.
All addition products were regioselectively formed as α-addition products. This is in
accord with the higher electron density at the carbon center in the α-position to nitrogen.
Therefore, the electrophilic attack of the allylic radical should be preferred at this position
and not at the γ-carbon atom. The latter attack should be also disfavored due to the sterical
hindrance.
Chapter 4. Summary 146
+
30%CdS/Al2O3 hνMeOH/CH2Cl2
X
HN +
9 - 13 a - c 14a - 18c 19- 22
R-H
X
N
H RH
X
HN
X
NH
X -H -F -Cl -Br -OCH3 9 10 11 12 13
Addition 14b-14c 15b-15c 16a-16c 17b-17c 18b-18cProduct
Hydrodimer - 19 20 21 22
Isolated yield21-85%
R:Me
a b c
Figure 4.3: Photocatalytic addition reaction between N-(1-adamantyl)-benzaldehyde imine
derivatives and cyclopentene, cyclohexene, and α-pinene.
In the second set of synthesis work, semiconductor photocatalyzed syntheses were
progressed to the synthesis of adamantane ring containing novel homoallylamine
derivatives. Adamantane derivatives receive great attention in synthetic and pharmaceutical
chemistry because of their diverse biological activity. Therefore it was of interest
synthesizing novel derivatives through semiconductor photocatalysis.
A series of novel homoallylamine derivatives were synthesized through CdS
photocatalyzed C-C coupling reactions between certain olefins (cyclopentene, cyclohexene
and α-pinene) and various N-(1-adamantyl)-benzaldehyde imines. The novel compounds
were identified by NMR, IR, MS, and some of them by X-ray crystal structure analysis like
16a and 16b. According to x-ray crystal structure analysis, the addition products are
present as enantiomeric pairs of two diastereomers.
Chapter 4. Summary 147
Figure 4.4: Crystal structures of 16a and 16b.
In the case of addition reactions of cyclohexene to various p-substituted N-(1-adamantyl)-
benzaldehyde imine derivatives the addition products were isolated in yields of 47-82%.
Whereas the highest yield was obtained from addition to the p-fluoro derivative with 82%,
the lowest yield belongs to the p-methoxy substituted compound with 47%. The
hydrodimer of the imine was observed only for 11 in significant amount and in traces for
12. The hydrodimer formation for 11 is diastereoselective affording one identical
diastereomer in the case of cyclopentene and α-pinene addition, and the other diastereomer
in the case of cyclohexene addition.
The addition of α-pinene was also performed with chloro-, fluoro-, bromo-, methoxy-
substituted and unsubstituted derivatives of N-(1-adamantyl)-benzaldehyde imine in
satisfactory to good yields (21-85%). In this case, the highest yields were obtained for the
p-bromo substituted imine with 85% and for p-fluoro compound with 81%. The
hydrodimers of the imine were detected only by HPLC but not isolated except the
hydrodimer of 11. The unsubstituted derivative of the imine yielded only the addition
product, as it has been noted for the cyclohexene addition as well.
In conclusion, in the synthesis part of this work demonstrates that photoinduced charge
separation could be utilized for new atom economic organic syntheses. Although no
information on biological activity of the novel compounds is available, according to present
knowledge some of them posses promising structural aspects.
16a 16b
Chapter 5. Zusammenfassung 148
CHAPTER 5 5. Zusammenfassung Das Ziel dieser Arbeit war es, die allgemeine Anwendbarkeit der kürzlich berichteten CdS
katalysierten Photoaddition von zyklischen Olefinen an Imine zu untersuchen. Weiterhin
wurde der früher untersuchte Effekt der Steigerung der Reaktionsgeschwindigkeit durch
kovalente Bindung von CdS auf Kieselgel (SEMSI Effekt) auf das System CdS-
Aluminiumoxid erweitert.
C NH
Ar
Ar
MeOHC N
H
HAr
ArCH
CHAr NHAr
Ar NHAr+
CdS/hν+
Im ersten Teil dieser Arbeit wurde der elektronische Halbleiter-Träger-Wechselwirkung
(SEMSI) für Aluminiumoxid gestützte CdS-Pulver untersucht. Im Fall des Aluminiumoxid
gestützten CdS wurden eine geringe Vergrößerung der Bandlücke (0.02-0.06 eV) und eine
Verschiebung der Bandkante beobachtet (Abbildung 5.1). Die größeren
Bandlückenverschiebungen wurden bei den von saurem Aluminiumoxid gestützten
Photokatalysatoren (30AII and 10AII) und bei dem von neutralem
Aluminiumoxid gestützten Katalysator, welcher in einer stärker basischen
Imprägnierungslösung hergestellt wurde (30NII25). Durch XRD-Analysen und
hochaufgelöste Transmissionselektronenmikrographie konnte die kubische Struktur der
CdS-Pulver mit einer Kristallgröße von 8-20 nm ohne Zweifel aufgeklärt werden.
(5.1)
Chapter 5. Zusammenfassung 149
Da aus der Literatur bekannt ist, daß die für quasi-Fermi Niveau Messungen angewendete
Methode von der Lichtintensität abhängig ist, wurden entsprechende Versuche
durchgeführt. Es zeigte sich, daß unter vorgegebenen experimentellen Bedingungen die
erhaltenen Werte nicht von der Lichtintensität abhängig waren. Zusätzlich wurde
herausgefunden, daß weder die An- noch die Abwesenheit eines Reduktionsmittels einen
signifikaten Effekt hervorrief. Dies läßt vermuten, daß die photoproduzierten Löcher das
Gittersulfid zu elementaren Schwefel oxidieren, wie auch durch XPS Analyse bestätigt
wurde.
CdS-A 10NII 30NII25 30BII 30AII 10AII
2,5
2,0
1,5
1,0
0,5
0,0
-0,5 ⎯ ⎯ ⎯ ⎯ ⎯ ⎯
⎯ ⎯ ⎯ ⎯ ⎯ ⎯
2.462.432.412.482.452.39
+ 2.07+ 2.06+ 2.04+ 1.97 + 2.10+ 2.10
- 0.36- 0.36- 0.35- 0.38- 0.41- 0.42
Photokatalysatoren
E(F
B)[V
]
Abbildung 5.1: Positionen der Bandkanten (+ 0.02 V) und die Bandlückenenergie (+ 0.01
eV) für die CdS-Photokatalysatoren bei pH=7.
Da die Bandkanten sich nicht wesentlich verschieben, und die Valenz- und Leitungsbänder
Schwefel- bzw. Cadmiumcharakter besitzen, unterscheiden sich die durch XPS bestimmten
Bindungsenergien sowohl für Cd3d als auch für S2p Elektronen nur geringfügig (0.4 eV).
Zeitaufgelöste Messungen der Photospannung zeigen, daß die Lebensdauer der
photogenerierten Oberflächenladungen von 0.76 µs auf 1.20 µs steigt, wenn CdS auf
Chapter 5. Zusammenfassung 150
neutrales Aluminiumoxid gestützt wird (siehe Tabelle 5.1). Parallel dazu steigt die
Bandlückenenergie von 2.39 auf 2.45 eV. In ähnlicher Weise steigt die
Reaktionsgeschwindigkeit der Olefinaddition (Gl. 5.1) ungefähr auf das Vierfache, wenn
statt ungestütztem CdS die Probe 10NII verwendet wird, und ungefähr auf das Sechsfache
im Fall von 30NII25 (Tabelle 5.2).
Photokatalysatoren Ebg
[eV]
Lebensdauer
[10-6 s]
Reaktionsgeschwindigkeit
[10-7 moll-1s-1]
CdS-A 2.39 0.76 0.24 50NII 2.42 0.75 0.25 30NII 2.43 0.86 0.36 10NII 2.45 1.20 0.84
Tabelle 5.1: Positionen der Bandkanten, Bandlückenenergien, und Lebensdauern für
ungestütztes CdS und 10-50% CdS/Al2O3(n) im Vergleich mit
Reaktionsgeschwindigkeiten.
Photokatalysatoren Ebg
[eV]
Lebensdauer
[10-5 s]
Reaktionsgeschwindigkeit
[10-7 moll-1s-1]
30AII 2.43 0.57 0.34 30NII 2.43 0.61 0.36 30NII25 2.48 0.64 1.97
Tabelle 5.2: Positionen der Bandkanten, Bandlückenenergien, und Lebensdauern für die
30Gew% Al2O3 gestützten Photokatalysatoren im Vergleich mit
Reaktionsgeschwindigkeiten.
Zusammenfassend wurde gefunden, daß im Fall von Aluminiumoxid-gestütztem CdS der
SEMSI Effekt nicht so stark wie bei Kieselgel-gestütztem CdS ist. Der Grund für diese
Tatsache sind die unterschiedlichen Elektronegativitäten von Al und Si, welche die
Elektronendichte am Trägersauerstoffatom beeinflussen. Die niedrigere Elektronegativität
von Al (1.47) gegenüber Si (1.74) verursacht eine geringere Änderung der
Chapter 5. Zusammenfassung 151
Elektronendichte an Sauerstoff und Cadmium, welche zu einer geringeren Verschiebung
der Positionen der Bandkanten führt.
Ph NPh R-H
MeOH
Ph NH
Ph
R
Ph NH
Ph
Ph NH
Ph
R
hν+
30% CdS/Al2O3
Addition in α-Position Addition in γ-Position
R: Me
Ausbeute% 67 72 48
Abbildung 5.2: Photokatalytische Additionsreaktion zwischen Zimtsäureanil und
Cyclopenten, Cyclohexen und α-Pinen.
Im zweiten Teil der vorliegenden Arbeit wurden neuartige Homoallylaminderivate über
Halbleiterphotokatalyse synthetisiert.
Im ersten Teil der synthetischen Arbeit wurde diese schon bekante Photoaddition auf das
α,β-ungesättigte Imin Zimtsäureanil erweitert, welches ein stickstoffterminiertes
konjugiertes offenkettiges System enthält, um die allgemeine Anwendbarkeit der
photokatalytischen Additionsreaktionen zwischen Iminen und Olefinen zu untersuchen.
Belichtung einer methanolischen Lösung von Zimtsäureanil in Gegenwart eines
CdS/Al2O3(n) Photokatalysators und eines Überschusses des Olefins erzeugt entsprechende
neuartige homoallylische sekundäre Amine, welches Produkte einer C-C-Kupplung
zwischen dem α-Aminozimtsäureradikal des Imins und des Allylradikals des Olefins sind
(Abbildung 5.2). Die Strukturzuordnung dieser neuen Substanzen erfolgte mittels NMR-,
IR- und MS-Analyse.
Die Addition erfolgte stets regioselektiv zu α-Additionsprodukten. Dies erfolgt in
Übereinstimmung mit der höheren Elektronendichte am Kohlenstoffzentrum in α-Position
zum Stickstoff. Deshalb sollte der elektrophile Angriff des Allylradikals bevorzugt in
Chapter 5. Zusammenfassung 152
dieser Position und nicht am γ-Kohlenstoffatom erfolgen. Der letztgenannte Angriff ist
ebenfalls aufgrund sterischer Hinderung benachteiligt.
+
30%CdS/Al2O3 hνMeOH/CH2Cl2
X
HN +
9 - 13 a - c 14a - 18c 19- 22
R-H
X
N
H RH
X
HN
X
NH
X -H -F -Cl -Br -OCH3 9 10 11 12 13
Additions- 14b-14c 15b-15c 16a-16c 17b-17c 18b-18cProdukt
Hydrodimer - 19 20 21 22
Ausbeute21-85%
R:Me
a b c
Abbildung 5.3: Photokatalytische Additionsreaktion zwischen N-(1-Adamantyl)-
benzaldehydiminderivaten und Cyclopenten, Cyclohexen, und α-Pinen.
Im zweiten Teil der synthetischen Arbeit wurden halbleiterphotokatalysierte Synthesen zur
Darstellung von Adamantylaminen weitergeführt. Adamantylamine erlangten in
synthetischer und pharmazeutischer Chemie wegen ihrer vielfältigen biologischen Aktivität
große Aufmerksamkeit. Daher war es von Interesse, neuartige Derivate durch
Halbleiterphotokatalyse zu synthetisieren.
Eine Reihe von neuartigen Homoallylaminderivaten wurde über CdS-photokatalysierte C-
C-Kupplungsreaktionen zwischen bestimmten Olefinen (Cyclopenten, Cyclohexen und α-
Pinen) und verschiedenen N-(1-Adamantyl)-benzaldehydiminen dargestellt. Die
Strukturzuordnung dieser neuen Substanzen erfolgte mittels NMR-, IR- und MS-Analyse,
und bei manchen, wie 16a und 16b, mittels Röntgenstrukturanalyse. Gemäß der
Röntgenstrukturanalyse liegen die Additionsprodukte als Enantiomerenpaare zweier
Diastereomere vor.
Chapter 5. Zusammenfassung 153
Abbildung 5.4: Kristallstrukturen von 16a und 16b.
Im Fall der Additionsreaktionen von Cyclohexen an verschiedene p-substituierte N-(1-
Adamantyl)-benzaldehydiminderivate konnten die Additionsprodukte in Ausbeuten von
47-82% isoliert werden. Dabei wurde die höchste Ausbeute bei der Addition an das p-
fluoro-Derivat mit 82% erhalten, und die niedrigste Ausbeute gehörte zu der p-
methoxysubstituierten Verbindung mit 47%. Das Hydrodimer des Imins konnte nur bei 11
in beträchtlichen Mengen beobachtet werden und in Spuren bei 12. Die Bildung des
Hydrodimers von 11 verläuft diastereoselektiv, wobei im Fall der Addition von
Cyclopenten und α-Pinen nur ein identisches Diastereomer und im Fall der Addition von
Cyclohexen nur das andere Diastereomer entsteht.
Die Addition von α-Pinen wurde ebenfalls mit chloro-, fluoro-, bromo-,
methoxysubstituierten und unsubstituierten Derivaten von N-(1-Adamantyl)-
benzaldehydimin mit befriedigenden bis guten Ausbeuten (21-85%) durchgeführt. In
diesem Fall wurden die höchsten Ausbeuten mit dem p-bromsubstituierten Imin mit 85%
und mit dem p-fluorsubstituierten Imin mit 81% erzielt. Die Hydrodimere des Imins
wurden nur mittels HPLC nachgewiesen und mit Ausnahme von 11, nicht isoliert. Das
unsubstituierte Iminderivat ergab nur das Additionsprodukt, wie bei der oben genannten
Addition von Cyclohexen.
16a 16b
Chapter 5. Zusammenfassung 154
Zusammenfassend zeigt der synthetische Teil der vorliegenden Arbeit, dass
photoinduzierte Ladungstrennung für neue atomökonömische organische Synthesen
genutzt werden kann. Obwohl die biologische Aktivität dieser Verbindungen noch
unbekannt ist, besitzen einige von ihnen, basierend auf unserem jetzigen Wissenstand,
vielversprechende Strukturmerkmale.
Chapter 6. Experimental 155
CHAPTER 6 6. Experimental Section
6.1. General Methods
All preparations, synthesis and NMR measurements were carried out under nitrogen
atmosphere by standard Schlenk techniques.
6.1.1. Irradiation Apparatus and Lamps
All preparative irradiations were performed under nitrogen atmosphere in a Pyrex-
immersion lamp apparatus (sample volume: 100-250 ml) with a tungsten-halogen lamp
(100W, 12V, λ>350 nm, Osram) (Figure 6.1). The lamp shaft of the apparatus is made of
quartz glass which is surrounded by a cooling jacket. The suspension was effectively
stirred with a magnetic stirrer and cooled by circulating water through the cooling jacket to
provide a constant temperature during the irradiation. 1 ml samples were taken from the
side fixed neck closed with a tight rubber septum in order to follow the reaction progress,
and after filtering off the catalyst through a micropore-filter (Whatman, Nylon membrane,
diameter: 4 mm, pore-size: 0.45 µm), they were injected to analytical HPLC or TLC
analysis was carried out.
All irradiations to determine photocatalytic activities were carried out in a 15 ml quartz
cylindrical cuvette (Figure 6.2) placed on a scaled optical bench (Figure 6.3) (at a 30 cm
distance from the lamp). Irradiation was performed with an Osram XBO 150W Xenon-arc
lamp (intensity I0 (400-500 nm) = 2.10-6 Einstein.s-1.cm-1).
Chapter 6. Experimental 156
During the irradiation, the reaction mixture was cooled by water circulation through the
surrounding cooling jacket of cylindrical cuvette.
Quasi-Fermi level determinations were performed in a three necked round bottom Pyrex
flask placed on the optical bench at 30 cm distance from the irradiation source (150 W
XBO lamp). For the light intensity effect investigations, various neutral-density filters of
different transmission were used.
Figure 6.1: Pyrex immersion lamp apparatus
Chapter 6. Experimental 157
Figure 6.2: Cylindrical quartz cuvette
Figure 6.3: Optical bench
Chapter 6. Experimental 158
6.1.2. Solvents and substances
All solvent were p.a. grade and deuterated solvents were also degassed before use; samples
for NMR measurements were prepared under nitrogen.
Substances for CdS Preparation:
CdSO4·8/3H2O (Riedel de Haën), Na2S·xH2O (Fluka)
Support Materials:
Aluminum oxide activated, Neutral:
Aldrich, [19,997-4], Typ 507C, Brockmann I (Standard)
Grain size ~ 150 mesh, 58 A°, pH of aqueous suspension: 6.8 (for 100 g/l)
(For OH-group density and specific surface area values see Section 6.1.3.9)
Aluminum oxide activated, Acidic:
Aldrich, [19,996-6], Typ 504C, Brockmann I (Standard)
Grain size ~ 150 mesh, 58 A°, pH of aqueous suspension: 5.0 (for 100 g/l)
(For OH-group density and specific surface area values see Section 6.1.3.9)
Aluminum oxide activated, Basic:
Aldrich, [19,944-3], Typ 5016, Brockmann I (Standard)
Grain size ~ 150 mesh, 58 A°, pH of aqueous suspension: 10.0 (for 100 g/l)
(For OH-group density and specific surface area values see Section 6.1.3.9)
Silica Grace Type 432, Neutral: particle size: 30-60 µm, pore size: 17 nm.
(For OH-group density and specific surface area values see Section 6.1.3.9)
Silica Aerosil 200, Degussa: pH: 3.5-5.5, SiO2 content wt% 99.0–100.5
(For OH-group density and specific surface area values see Section 6.1.3.9)
Olefinic Substances: Cyclopentene (Acros), cyclohexene (Acros), (1S)-(-)-α-pinene
(Acros) were distilled and stored under nitrogen prior to use.
Amines and Aldehydes: Aniline (Merck), 1-Adamantylamine (Aldrich), p-
Fluorobenzaldehyde (Acros), p-Bromobenzaldehyde (Aldrich), p-Chlorobenzaldehyde
(Acros), Benzaldehyde (Acros), Anisaldehyde (Fluka), trans-Cinnamaldehyde (Acros).
Chapter 6. Experimental 159
6.1.3. Spectroscopic and analytical methods
6.1.3.1. NMR Spectroscopy
All NMR spectra were recorded on JEOL FT-JNM-EX 270 or JEOL FT-JNM-LA 400
spectrometers at RT.
6.1.3.2. Mass Spectroscopy
Mass spectra were recorded on JEOL JMS 700 (EI 70 eV, FD 2 kV).
6.1.3.3. IR Spectroscopy
IR spectra were recorded on Perkin-Elmer 16 PC FT-IR as KBr pellets or in CaF2 cuvettes.
6.1.3.4. Diffuse Reflectance Spectroscopy
Diffuse reflectance spectra were recorded on a Shimadzu UV-3101 PC, UV-Vis-NIR
scanning spectrophotometer equipped with a diffuse reflectance accessory. BaSO4 or Al2O3
were used as reference. For all CdS photocatalyst powders, measured reflectance values
were converted by the instrument software to the Kubbelka-Munk function (F(R∞)) and
transformed to the modified Kubelka-Munk functions for direct semiconductors by help of
the Origin® program.
All DRS measurements were performed with the pure CdS substance in order to determine
band-gap energy values. However, in the case of optimum catalyst amount determinations
for photocatalytic activity measurements, in order to prepare various concentrations, CdS
samples were diluted into BaSO4 and ground finely in a ball mill and reflectance spectra
were recorded for these diluted substances.
6.1.3.5. XRD
XRD measurements were performed using a Huber-diffractometer with Cu-Kα radiation
(λ=1.5048 Å).
Chapter 6. Experimental 160
6.1.3.6. Transmission Electron Microscopy
The analysis was carried out in the Central Facility for High Resolution Electron
Microscopy of Friedrich-Alexander University Erlangen-Nürnberg
Instrument: Philips CM 30 T/STEM, operated at 300 kV accelerating voltage.
Preparation of samples for TEM:
• Suspending powders in MeOH
• Treatment in an ultrasonic bath for approximately 30 s
• Dropping the suspension on a C-filmed Cu-Net
• Drying under air
Measurement of CdS-grain size:
• Darkfield-illustration with a section of inflection-rings (diffuse, nanocrystalline
powder)
• Assessing of size from final picture-screen (Ring, enlargement)
6.1.3.7. XPS
X-ray photoelectron spectra were measured on a Phi 5600 ESCA spectrometer (pass energy
of 23.50 eV, Al standard, 300.0 W, 45.0°)
6.1.3.8. Photo-EMF Measurements (P-EMF)
Measurements were performed by Dr. Cornelia Damm/Doz. Dr.Israel at Martin-Luther-
Universität Halle-Wittenberg, Institut für Organische Chemie, Merseburg.
Sample preparation:
100 mg of the powder were dispersed in 3 g of a solution of PVB Mowital B 30 HH in 1,2-
Dichlorethane (10 wt% polyvinyl butyrate).The mixture was cast on a hydrophobic glass
slide having a surface area of 26 cm2 and dried in a solvent atmosphere. After drying the
dispersion layer was removed from the glass support and stored in vacuum (5 Torr) at room
temperature for 9h. The dispersion layers contain about 25 wt% of the pigment.
Chapter 6. Experimental 161
Figure 6.4: Registration of a P-EMF signal from a laser pulse irradiated semiconductor
sample; (1) Sample, (2) Transparent electrode (conducting glass), (3) Metal electrode, (4)
Insulating foil. [1]
Photo-EMF measurements:
From the dispersion layer pieces having a diameter of 1 cm were cut and placed in the
Photo-EMF apparatus. To get information about the whole decay process Photo-EMF
measurements in two time ranges were performed: (1) µs range to record the fast decay
processes, (2) ms range to record the slow decay processes.
Conditions of the Photo-EMF measurements:
Wavelength: 337 nm (Nitrogen laser PNL 100), about 2.7x1013 quanta per flash, samples
have total absorption, Temperature: 25°C.
Chapter 6. Experimental 162
6.1.3.9. OH-group Densities and Specific Surface Areas
Thermogravimetry (TGA) and BET measurements were carried out in Institute of
Theoretical Chemistry, by R. Müller from the research group of Prof. Dr. Schwieger.
Acidic Al2O3 : Removal of weight from 23.2166 mg between 200 and 1000°C: 0.6103 mg
OH group density: 6.22 OH/nm2, BET: 149 m2 / g
Figure 6.5: TGA data of Al2O3(a).
Chapter 6. Experimental 163
Basic Al2O3: Removal of weight from 16.4463 mg between 200 and 1000°C: 0.2890 mg
OH group density: 4.28 OH/nm2, BET: 145 m2 / g
Figure 6.6: TGA data of Al2O3(b).
Chapter 6. Experimental 164
Neutral Al2O3: Removal of weight from 18.7320 mg between 200 and 1000°C: 0.3827 mg
OH group density: 3.83 OH/nm2, BET: 189 m2 / g
Figure 6.7: TGA data of Al2O3(n).
Chapter 6. Experimental 165
SiO2 Grace432: Removal of weight from 7.7832 mg between 200 and 1000°C: 0.1162 mg
OH group density: 1.72 OH/nm2, BET: 308 m2 / g
Figure 6.8: TGA data of SiO2 Grace Type 432.
Chapter 6. Experimental 166
SiO2 Aerosil200: Removal of weight from 2.8415 mg between 200 and 1000°C: 0.01967
mg, OH group density: 1.65 OH/nm2, BET: 148 m2 / g
Figure 6.10: Recorded TGA data of SiO2 Aerosil Type 200.
6.1.3.10. Elemental Analysis
Elemental analyses were performed with a Carlo Erba Elemental Analyzer Model 1108 for
CdS samples and with Carlo Erba Elemental Analyzer Model 1106 for all organic
compounds.
Chapter 6. Experimental 167
6.1.3.11. Cyclic Voltammetry
Cyclic voltammetry measurements were performed with a BAS Epsilon EC instrument
with a standard three-electrode cell under argon atmosphere at RT. The concentration of
imine substance was 10-3M. NBu4PF6 (10-1M) was used as electrolyte. Potentials were
referenced to the NHE.
Three-electrode cell set-up:
Working electrode: glassy carbon ROTEL A
Reference electrode: SCE (Potential values were taken by the saturated KCl system)
Auxiliary electrode: Pt wire
6.1.3.12. HPLC
Analytical: SHIMADZU LC-10ATvp Pump, with FCV-10ALvp solvent mixer unit,
injection unit with 20µl sample loop, Column: SUPELCO Discovery-C18 High-pressure
column, Eluent: corresponding eluent systems were depicted in synthesis section for each
sample. Detector: SPD-M 10Avp Diode Array Detector
Preparative: KNAUER HPLC pump 64, preparative pump head with 1ml sample loop;
Column: Nucleosil 120 C18 (250x32mm, 5µm, Knauer); Eluent: CH3CN/H2O (5/1; v/v);
flow rate: 37 ml/min; Detector: Knauer UV-Vis Filter-Photometer (λ=254 nm).
6.1.3.13. TLC
SiO2: (Fluka) with fluorescence indicator 254 nm, layer thickness: 0.2 mm on aluminium
cards
Al2O3: (Fluka) with fluorescence indicator 254 nm, layer thickness: 0.2 mm on TLC-PET
foils
6.1.3.14. Preparative Column Chromatography
SiO2: (Fluka) Silica gel 60, particle size: 0.04-0.0063 mm, Activity according to
Brockmann and Schodder: 2-3
Al2O3: (Acros), neutral, particle size: 52-200 µm.
Chapter 6. Experimental 168
6.2. Quasi-Fermi Level Measurements Used materials and devices:
0.01 M, 0.1 M, 1 M and 2 M of NaOH solutions and HNO3 solutions
30 mg of powder
6 mg of Methylviologenedichloride
0.1 M of KNO3 solution (75 ml)
pHmeter, multimeter
light source: XBO 150W lamp
working electrode: platinum plate with a large surface
reference electrode: Ag/AgCl
Figure 6.11: Schematic illustration of photovoltage measurement cell
Experimental method:
30 mg of CdS powder in 75 ml of KNO3 solution were sonicated in a three-necked flask
under vacuum for 15 minutes. Thereafter experimental set up was arranged and the system
kept under N2. Initial pH values of 7.0-7.5 were found for all materials. The pH value of
Chapter 6. Experimental 169
the suspension was adjusted by dropping HNO3 solution into the suspension for obtaining
pH ≅ 3-3.5 as initial pH value. Thereafter MV2+ was added to the suspension (addition of
MV2+ before acidification may cause an experimental error because at higher pH values
MV2+ is not stable), light source was switched on and “titration” was carried out until
observation of the blue color of MV+•.
6.2.1. Influence of Hole Scavengers
The measurements were carried out as described above except by adding CH3CO2Na or
Na2SO3 to the suspension. Experiments were performed with 50% neutral alumina
supported CdS (50NII).
Investigation of S0 formation: The measurements were carried out as described above for
the absence of a hole scavenger with 50NII. Further details are described in theoretical part
(Chapter 2.3.2.1). The dried CdS powder was pressed into a pellet (200 kp/cm2) and
subjected to XPS analysis.
6.2.2. Influence of Light Intensity
The measurements were carried out in the absence of a hole scavenger as described above.
In all cases a 400 nm cut-off filter was inserted into the light beam. Light intensity was
varied with various neutral density filters (%T: 70, 50, 43, 35, 28, 12). The light intensity
of the 150 W XBO lamp was measured with a Radiant Power/Energy Meter, Model 70260
(Oriel Instruments) by placing the sensor (at λ=250-600 nm) at the distance of 30 cm
(where the cuvette is usually placed) from the lamp. A water filter was also used between
lamp and cuvette for removing IR radiations. The experiments were performed with 50NII.
Chapter 6. Experimental 170
6.3. Synthesis of CdS Photocatalysts
6.3.1. Unsupported CdS (CdS-A)
CdSO4·8/3H2O were dissolved in aqueous NH3 (10%). Na2S·xH2O were dissolved in water
and added dropwise to the CdSO4 solution within a period of 1,5 h. The resulting yellow
suspension was stirred for 20 h. After separation by suction filtration, the residue was
washed with water to constant pH (pH=7), dried over P2O5 in a vacuum desiccator. After
drying, the powder was ground in an agate mortar and stored under N2 (see Table 6.1).
6.3.2. SiO2 supported CdS
10 g of SiO2 and CdSO4·8/3H2O (5.33 g, 20.8 mmol) were stirred overnight in 150 ml
aqueous NH3 (10%). Na2S·xH2O (5.72 g, 20.8 mmol) were dissolved in 50 ml water and
added dropwise to the CdSO4/ SiO2 mixture within a period of 1,5 h. The resulting yellow
suspension was stirred for 20 h. After separation by suction filtration, the residue was
washed with water to constant pH (pH=7) and dried over P2O5 in a vacuum desiccator.
After drying, the powder was ground in an agate mortar and stored under N2.
6.3.3. Al2O3 supported CdS
Neutral Al2O3 supported CdS powders:
Alumina-supported photocatalysts containing 50, 30, and 10 wt% of CdS were prepared by
impregnating Al2O3 with cadmium sulfate and precipitation with sodium sulfide.
Aluminum oxide (neutral) and CdSO4·8/3H2O were stirred overnight in aqueous NH3
(10%) (Alumina was stirred in ammonia for 8h previously). Na2S was dissolved in water
and added drop wise to the CdSO4/Al2O3 mixture within a period of 1,5 h. The resulting
yellow suspension was stirred for 20 h. After separation by suction filtration, the residue
was washed with water to constant pH (pH=7), dried over P2O5 in a vacuum desiccator.
After drying, the powder was ground in an agate mortar and stored under N2 (see Table
6.1).
Chapter 6. Experimental 171
Photocatalyst CdSO4 10% NH3 Na2S H2O Al2O3(n)
CdS-A 12.85 g (89.2 mmol)
150 ml 11.15 g (40.61 mmol)
50 ml -
10N 1.77 g (6.92 mmol)
50 ml 1.9 g (6.92 mmol)
20 ml 10 g
30N 5.33 g (20.8 mmol)
150 ml 5.72 g (20.8 mmol)
50 ml 10 g
50N 8.90 g (34.6 mmol)
250 ml 9.53 g (34.6 mmol)
100 ml 10 g
Table 6.1: Amounts of materials employed for preparation of unsupported and neutral
alumina supported CdS powders.
Acidic Al2O3 supported CdS powders:
As described above but employing acidic alumina (Al2O3 10A and Al2O3 30A
corresponding to 10% and 30% alumina) (see Table 6.2).
Basic Al2O3 supported CdS powder:
As described above but employing basic alumina (Al2O3 30B corresponding to 30%
alumina) (see Table 6.2).
Photocatalyst CdSO4 10% NH3 Na2S H2O Al2O3(a)/(b)
10A 1.77 g (6.92 mmol)
50 ml 1.9 g (6.92 mmol)
20 ml 10 g
30A 5.33 g (20.8 mmol)
150 ml 5.72 g (20.8 mmol)
50 ml 10 g
30B 5.33 g (20.8 mmol)
150 ml 5.72 g (20.8 mol)
50 ml 10 g
Table 6.2: The used amounts of materials for preparation of acidic and basic alumina
supported CdS powders.
Neutral Al2O3 supported CdS powders prepared in 25% NH3 solution:
As described above but using 25% NH3 (see Table 6.3)
Chapter 6. Experimental 172
Photocatalyst CdSO4 25% NH3 Na2S H2O Al2O3(n)
30N25 5.33 g (20.8 mmol)
150 ml 5.72 g (20.8 mmol)
50 ml 10 g
Table 6.3: Amounts of materials employed for preparation of neutral alumina supported
CdS in more basic solution.
6.4. Photocatalytic Activity Measurements
All mechanistic investigations with CdS photocatalysts were performed in a 15 ml quartz
cylindrical cuvette (Figure 6.2) placed on an optical bench (Figure 6.3). During irradiation
(full light) the cuvette was cooled with water to obtain a constant temperature. Prior to
irradiation the reaction mixture was prepared by sonicating 50 mg (0.20 mmol) of N-(4-
chlorobenzylidene)-4-chloraniline, 1 ml (11.4 mmol) of cyclopentene, and various amounts
of CdS (see Table 6.4) in 10 ml of MeOHabs in a Schlenk-tube for 15 min. The suspension
was then transferred under nitrogen to the quartz cuvette with the help of a Pasteur pipette.
A 0.1 ml sample was withdrawn and after filtering off the catalyst through a micropore
filter, the solution was analyzed by analytical HPLC (Eluent: CH3CN/H2O=70/30 (v/v),
flow rate: 0.5 ml/min).
Photocatalyst
Amount of photocatalyst
taken for rate determination
[mg/11ml]
CdS-A 20 50N 30 30N 30 10N 55 30A 30 10A 36 30N25 34
Table 6.4: Photocatalyst amounts of the same Kubelka-Munk function (proportional to
absorbance) at 490 nm (see also Chapter 2.4).
Chapter 6. Experimental 173
6.5. Syntheses
6.5.1. Addition reactions with N-Cinnamylideneaniline
Ph NPh R-H
MeOHPh N
HPh
R
+ 30% CdS-Al2O3
hν
R:Me
6 a-c 7a-c
a b c
6.5.1.1.Synthesis of N-cinnamylideneaniline (6)
N-cinnamylideneaniline was synthesized from trans-cinnamaldehyde and freshly distilled
aniline in chloroform under nitrogen atmosphere at RT and recrystallized from MeOH.
Elemental Analysis: C15H13N (207.27) Calculated: C 86.92; H 6.32; N 6.76
Found : C 86.48; H 7.07; N 6.94
MS (FD, 2kV, in CHCl3, m/z): 207 [M+]
6.5.1.2.Synthesis of N-(1-(cyclopent-2-enyl)-3-phenylallyl)benzenamine (7a)
NH1
23
4
56 7
89 11
1213
1415
16
10
17 21
2019
18
7a
Chapter 6. Experimental 174
1 g (4.82 mmol) of 6 and 0.5 g (1.03 mmol CdS) of 30%CdS/Al2O3 (n) were suspended in
absolute MeOH (80 ml) in a Pyrex immersion lamp apparatus by sonication for 15 min
under N2. Cyclopentene (17 ml, 192.8 mmol) was added after sonication and the
suspension was irradiated until the complete consumption of 10 (5 d). The reaction
progress was followed by analytical HPLC (Eluent: CH3CN/H2O=70/30 (v/v), flow-rate:
0.5 ml/min) and TLC analysis. After complete consumption of 6, irradiation was stopped
and the catalyst powder was filtered off from the mixture through a P4-frit system under
N2. Solvent was evaporated at reduced pressure and the addition product was isolated by
preparative column chromatography (packing material; neutral alumina, eluent; n-
hexan/CH2Cl2 (5/2; v/v)) under N2. The obtained diastereomeric mixture of 7a was injected
to the preparative HPLC (Eluent: CH3CN/H2O (5/1; v/v); flow rate: 37 ml/min) to separate
each diastereomer.
Isolated yield of 7a: 873 mg (67 %), diastereomeric mixture, yellow oil.
IR (CH2Cl2, CaF2) cm-1: 3415 (NH), 3053 (CHAr), 2986, 2851 (CH), 1421, 1503, 1601
(C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 1.72-1.80 (m, 1H, H18I/II), 1.99-2.06 (m, 1H,
H18´I/II), 2.33-2.36 (m, 2H, H19I/II), 3.03-3.10 (m, 1H, H17I), 3.11-3.30 (m, 1H, H17I),
3.70 (s, 1H, N-H), 3.84-3.90 (t, 1H, H9I), 3.97-4.04 (t, 1H, H9II), 5.68-5.73 (m, 1H,
H20I/II), 5.86-5.92 (m, 1H, H21I/II), 6.09-6.18 (d of d, 1H, H8I), 6.18-6.27 (d of d, 1H,
H8II), 6.50-6.56 (d, 1H, H7I), 6.57-6.59 (d, 1H, H7I), 6.59-6.06 (d, 2H, H12,16I/II), 6.06-
6.63 (t, 1H, H14I/II), 7.08-7.16 (t, 2H, H15,13I/II), 7.18-7.19 (t, 1H, H4I/II), 7.22-7.29 (t,
2H, H3,5I/II), 7.31-7.34 (d, 2H, H2,6I/II). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 26.3 (C18I), 26.4 (C18II), 32.0 (C19I), 32.4
(C19II), 51.1 (C17I), 51.3 (C17II), 58.3 (C9I), 59.6 (C9II), 113.1 (C12,16I), 113.4
(C12,16II), 116.8 (C14I), 117.0 (C14II), 126.3 (C2,6I/II), 127.1 (C4I), 127.2 (C4II), 128.4
(C3,5I/II), 129.1 (C13,15I/II), 130.0 (C20,7I/II), 130.7 (C8I/II), 134.3 (C21I/II), 137.0
(C1I/II), 147.7 (C11I/II).
Elemental Analysis: C20H21N (275.39) Calculated: C 87.23; H 7.69; N 5.09
Found : C 86.23; H 8.61; N 6.31
MS (FD, 2kV, in CHCl3, m/z): 275 [M+]
Chapter 6. Experimental 175
6.5.1.3.Synthesis of N-(1-(cyclohex-2-enyl)-3-phenylallyl)benzenamine (7b)
7b
NH1
23
4
56 7
89 11
1213
1415
16
10
17 21
2019
18
22
Analogous to the preparation of 7a but using cyclohexene (20 ml, 192.8 mmol). Irradiation
for 4 d, isolation by column chromatography under N2 (packing material; neutral alumina,
Eluent; n-hexan/CH2Cl2=5/1 (v/v))
Isolated yield of 7b: 1.01 g (72 %), diastereomeric mixture, yellow oil
IR (CH2Cl2, CaF2) cm-1: 3418 (NH), 3053 (CHAr), 2986, 2860 (CH), 1421, 1504, 1601
(C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 1.55-1.65 (m, 2H, H18,18´I/II), 1.85-1.94 (m, 2H,
H19I/II), 2.09-2.11 (br, 2H, H20I/II), 2.58-2.61 (br, 1H, H17I/II), 3.89 (s, 1H, N-H), 3.96-
3.99 (t, 1H, H9I), 4.02-4.04 (t, 1H, H9II), 5.71-5.74 (d, 1H, H22I), 5.77-5.80 (d, 1H,
H22II), 5.91-5.92 (m, 1H, H21I), 5.96-5.97 (m, 1H, H21II), 6.22-6.25 (d, 1H, H8I), 6.27-
6.30 (d, 1H, H8II), 6.61-6.68 (d, 1H, H7I/II), 6.70-6.71 (d, 2H, H12,16I/II), 6.73-6.76 (t,
1H, H14I/II), 7.19-7.27 (t, 2H, H15,13I/II), 7.28-7.29 (t, 1H, H4I/II), 7.31-7.34 (t, 2H,
H3,5I/II), 7.35-7.44 (d, 2H, H2,6I/II). 13C-NMR (400 MHz, CDCl3): δ (ppm) = 21.7 (C19I/II), 24.8 (C18I), 25.2 (C20I/II), 26.5
(C18II), 40.8 (C17I), 40.9 (C17II), 58.9 (C9I), 59.7 (C9II), 113.0 (C12,16I), 113.4
(C12,16II), 116.8 (C14I), 117.2 (C14II), 126.3 (C2,6I/II), 126.8 (C22I), 127.2 (C4I/II),
128.3 (C3,5I/II; C22II), 128.5 (C13,15I/II), 129.0 (C21I), 129.9 (C7I; C8I/II), 130.5
(C21II), 131.1 (C7II), 137.0 (C1I/II), 147.9 (C11I/II).
Elemental Analysis: C21H23N (289.41) Calculated: C 87.15; H 8.01; N 4.84
Found : C 85.74; H 7.71; N 6.67
MS (FD, 2kV, in CHCl3, m/z): 290 [M+]
Chapter 6. Experimental 176
6.5.1.4.Synthesis of N-(1-(4,6,6-trimethylbicyclo[3.1.1]hept-3-en-2-yl)-3-
phenylallyl)benzenamine (7c)
7c
NH1
23
4
56 7
89 11 12
13
1415
16
10
1721
2019
18
2226
2423
25
Analogous to the preparation of 7a but using α-pinene (23 ml, 192.8 mmol). Irradiation for
2d (since decomposition of the product was observed before consumption of the imine,
irradiation was stopped just before decomposition started), isolation by column
chromatography under N2 (packing material; neutral alumina, eluent; n-hexan/CH2Cl2=3/2
(v/v))
Isolated yield of 7c: 798 mg (48 %), diastereomeric mixture, yellow oil
IR (CH2Cl2, CaF2) cm-1: 3420 (NH), 3026 (CHAr), 2926, 2868 (CH), 1503, 1601 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 0.89 (s, 3H, H23I/II), 1.11 (m, 2H, H19I), 1.16 (m,
2H, H19II), 1.39 (s, 3H, H24I/II), 1.75 (s, 3H, H26I/II), 2.06 (m, 1H, H20I/II), 2.20 (m, 2H,
H18,18´I/II), 2.40 (br, 1H, H17I/II), 3.84 (s, 1H, N-H), 3.85-3.98 (t, 1H, H9I/II), 5.32 (d,
1H, H21I), 5.49 (d, 1H, H21II), 6.07-6.16 (d of d, 1H, H8I), 6.19-6.30 (d of d, 1H, H8II),
6.57-6.59 (d, 1H, H7I/II), 6.64-6.72 (m, 3H, H12,16;14I/II), 7.14-7.27 (m, 3H,
H15,13;4I/II), 7.30-7.43 (m, 4H, H3,5; 2,6I/II). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 20.4 (C24), 22.9 (C25), 26.9 (C26), 27.9 (C23I),
31.4 (C23II), 40.6 (C18I/II), 42.7 (C19I/II), 46.5 (C20I/II), 47.3 (C17I/II), 58.1 (C9I), 59.0
(C9II), 113.2 (C12,16I/II), 116.9 (C14I/II), 126.3 (C2,6I/II), 127.4 (C21I/II), 128.3
(C3,5I/II), 129.1 (C13,15I/II), 130.2 (C4I/II), 130.7 (C7I/II), 131.3 (C8I/II), 131.6
(C22I/II), 137.0 (C1I/II), 146.9 (C11I), 147.7 (C11II).
Elemental Analysis: C25H29N (343.5) Calculated: C 87.41; H 8.51; N 4.08
Found : C 87.59; H 8.89; N 4.37
MS (FD, 2kV, in CHCl3, m/z): 344 [M+]
Chapter 6. Experimental 177
6.5.2. Addition reactions with N-Adamantyl-p-X-benzaldehyde imine
(X: -H, -F, -Cl, -Br, -OCH3)
6.5.2.1. Synthesis of N-Adamantyl-p-X-benzaldehyde imine derivatives
(X: -H, -F, -Cl, -Br, -OCH3)
p-Substituted N-adamantyl-benzaldehyde imine derivatives were synthesized according to
references [2] and [3]. Corresponding aldehydes (4-fluorobenzaldehyde, 4-
chlorobenzaldehyde, 4-bromobenzaldehyde, benzaldehyde, anisilaldehyde) (19.87 mmol)
were added into a solution of 1-adamantylamine (19.87 mmol) in MeOH (aldehyde was
dissolved in MeOH and added into the amine solution slowly dropwise) and the mixture
was heated under reflux for 30 min. After solvent evaporation all imines were
recrystallized from MeOH.
N-Adamantyl- benzaldehyde imine (9)
Elemental Analysis: C17H21N (239) Calculated: C 85.30; H 8.84; N 5.85
Found : C 85.40; H 9.03; N 5.89
MS (FD, 2kV, in CHCl3, m/z): 240 [M++1], for crystal structure data see Section 6.6.1.
N-Adamantyl-p-fluoro-benzaldehyde imine (10)
Elemental Analysis: C17H20FN (257) Calculated: C 79.34; H 7.83; N 5.44
Found : C 80.50; H 8.32; N 5.52
MS (FD, 2kV, in CHCl3, m/z): 258 [M++1], for crystal structure data see Section 6.6.2.
N-Adamantyl-p-chloro-benzaldehyde imine (11)
Elemental Analysis: C17H20ClN (274) Calculated: C 74.57; H 7.36; N 5.12
Found : C 74.46; H 7.61; N 4.93
MS (FD, 2kV, in CHCl3, m/z): 273 [M+-1], for crystal structure data see Section 6.6.3.
Chapter 6. Experimental 178
N-Adamantyl-p-bromo-benzaldehyde imine (12)
Elemental Analysis: C17H20BrN (317) Calculated: C 64.16; H 6.33; N 4.40
Found : C 64.92; H 7.27; N 4.47
MS (FD, 2kV, in CHCl3, m/z): 318 [M++1], for crystal structure data see Section 6.6.4.
N-Adamantyl-p-methoxy-benzaldehyde imine (13)
Elemental Analysis: C18H23NO (269) Calculated: C 80.26; H 8.61; N 5.20
Found : C 81.01; H 9.18; N 5.28
MS (FD, 2kV, in CHCl3, m/z): 270 [M++1], for crystal structure data see Section 6.6.5.
6.5.2.2. Addition reactions with N-Adamantyl-p-chloro-benzaldehyde imine
R:Me
a b c
+ R-H30%CdS/Al2O3 hνMeOH/CH2Cl2
Ad:
Ar: Cl
NAd Ar
HHN
Ad Ar
HR +
HNAd Ar
HNAd Ar
11 16a-c 20-20'
6.5.2.2.1. Cyclopentene addition to N-Adamantyl-p-chloro-benzaldehyde imine
250 mg (0.9 mmol) of 11 and 250 mg (0.52 mmol CdS) of 30%CdS/Al2O3(n) were
suspended in absolute MeOH (45 ml) in a Pyrex immersion lamp apparatus by sonication
for 15 min under N2. After addition of cyclopentene (10 ml, 113 mmol), absolute CH2Cl2
(45 ml), and 1-2 drops of HOAc, the suspension was irradiated until complete
Chapter 6. Experimental 179
consumption of 11 (70 h). The reaction progress was followed by analytical HPLC (Eluent:
CH3CN/CH2Cl2=90/10 (v/v), flow-rate: 0.5 ml/min) and TLC analysis.
After complete consumption of 11, irradiation was stopped and the catalyst powder was
filtered off from the mixture through a P4-frit system under N2. Solvent was evaporated at
reduced pressure. The addition product 16a and hydrodimer 20 were isolated by
preparative column chromatography (packing material; silica, eluent; CH2Cl2/n-hexan (5/2;
v/v)) from impurities. 16a and 20 were crystallized from CH3CN/n-pentan and
MeOH/CH3CN solvent mixtures, respectively (for crystal structure data, see Section 6.6.6
for 16a; Section 6.6.8-b for hydrodimer 20).
Isolated yield of 16a: 160 mg (51 %), diastereomeric mixture, light yellow oil.
16a
1516
17
1213
1411
18 22
2
6
21
10
9
4
20
58
19
1
7
3
NH
CH
Cl
IR (CH2Cl2, CaF2) cm-1: 3673 (NH), 2911, 2852 (CH), 1420, 1524, 1604 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 1.21-1.36 (m, 2H, H22), 1.37-1.54 (m, 12H,
H2,6,7,10,4,9), 1.80-1.93 (m, 3H, H8,3,H5), 2.25-2.26 (m, 2H, H21), 2.82 (m, 1H, H18),
3.65 (s, 1H, N-H), 3.74 (d, 1H, H11), 5.22-5.25 (m, 1H, H20), 5.70-5.73 (m, 1H, H19),
7.03-7.30 (m, aromatic protons). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 28.9 (C3,5,8), 29.3 (C22), 34.8 (C4,9,10), 36.2
(C21), 40.6 (C2,6,7), 41.6 (C1), 51.9 (C18), 53.4 (C11), 128.3 (C14,16,20), 128.7
(C19,13,17), 131.2 (C15), 138.0 (C12).
Elemental Analysis: C22H28ClN (341,92) Calculated: C 77.28; H 8.25; N 4.10 Found : C 77.05; H 8.95; N 3.88
MS (FD, 2kV, in CH2Cl2, m/z): 343 [M++1], 275 [M+-67]
Chapter 6. Experimental 180
20
NH HN
ClCl
5
6
3
2
11
10
87
4
112
13
149
1615
17 18
252419
2620
2122
23
27
28
29
35
3433
36
30
3132
IR (CH2Cl2, CaF2) cm-1: 3623 (NH), 2906, 2847 (CH), 1486, 1604 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 0.87-1.64 (m, 24H,
H18,28,24,34,22,32,20,30,25,35,26,36), 1.89-1.99 (br, 6H, H33,29,31,23,19,21), 3.68 (s,
2H, N-H), 3.81 (s, 2H, H7,8), 3.74 (d, 1H, H7), 7.03-7.34 (m, 8H, aromatic protons). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 29.5 ppm (C19,21,23,29,31,33), 36.5 ppm
(C20,22,26,30,32,36), 43.8 ppm (C18,24,25,28,34,35), 51.0 ppm (C17,27), 60.8 ppm (C7),
61.4 ppm (C8), 127.7 ppm (C2,6), 127.8 ppm (C11,13), 128.9 ppm (C3,5), 129.6 ppm
(C10,14), 131.6 ppm (C1), 132.3 ppm (C12), 143.6 ppm (C4), 144.4 ppm (C9).
Elemental Analysis: C34H42Cl2N2 (549,62) Calculated: C 74.30; H 7.70; N 5.10 Found : C 74.65; H 7.76; N 5.07
MS (FD, 2kV, in CHCl3, m/z): 550 [M+], 275 [M+-275]
Chapter 6. Experimental 181
6.5.2.2.2. Cyclohexene addition to N-Adamantyl-p-chloro-benzaldehyde imine
Analogous to 6.5.2.2.1 but using cyclohexene (10 ml, 98.6 mmol). The suspension was
irradiated until complete consumption of 11 (4 d). The reaction progress was followed by
analytical HPLC (Eluent: CH3CN/CH2Cl2=90/10 (v/v), flow-rate: 0.5 ml/min) and TLC
analysis. The addition product 16b and hydrodimer 20′ were isolated by preparative
column chromatography (packing material; silica, eluent; CH2Cl2/n-hexan (5/1; v/v)). 16b
and 20′ were crystallized from CHCl3/n-hexan/(CH3)3CCN solvent mixture (for crystal
structure data, see Section 6.6.7 for 16b; Section 6.6.8-a for hydrodimer 20′; for IR, NMR,
Elemental analysis and MS data of hydrodimer see Section 6.5.2.2.1)
Isolated yield of 16b: 200 mg (62 %), diastereomeric mixture, light yellow oil.
16b
1516
17
1213
14
11
18 23
2
6
22
10
9
4
21
58
20
19
7
3
NH
CH
Cl
1
IR (CH2Cl2, CaF2) cm-1: 3609 (NH), 2928, 2850 (CH), 1447, 1604 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 1.16-1.18 (m, 2H, H22), 1.29-1.34 (m, 2H, H23),
1.41-1.56 (m, 6H, H10,4,9), 1.59-1.63 (m, 6H, H2,6,7), 1.78-1.81 (m, 2H, H21), 1.85-1.94
(m, 3H, H8,5,3), 2.19-2.29 (m, 1H, H18), 4.12 (br, 2H, N-H,H11), 5.68-5.69 (m, 1H, H20),
5.72-5.73 (m, 1H, H19), 7.14-7.17 (m, 2H, H17,13), 7.21-7.25 (m, 2H, H16,14). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 17.8 (C8,5,3), 19.4 (C22), 23.8 (C10,4,9), 28.2
(C23), 30.9 (C2,6,7), 35.4 (C21), 39.9 (C1), 46.0 (C18I), 54.8 (C18II), 64.0 (C11), 126.2
(C16,14), 126.7 (C20), 127.8 (C17,13), 128.6 (C19), 128.8 (C15), 129.5 (C12).
Elemental Analysis: C23H30ClN (355,94) Calculated: C 77.61; H 8.50; N 3.94 Found : C 75.55; H 8.37; N 4.12
MS (FD, 2kV, in CH2Cl2, m/z): 357 [M++1], 275 [M+-81]
Chapter 6. Experimental 182
6.5.2.2.3. α-Pinene addition to N-Adamantyl-p-chloro-benzaldehyde imine
Analogous to 6.5.2.2.1 but using α-pinene (10 ml, 82.8 mmol). The suspension was
irradiated until complete consumption of 11 (3 d). The reaction progress was followed by
analytical HPLC (Eluent: CH3CN/CH2Cl2=90/10 (v/v), flow-rate: 0.5 ml/min) and TLC
analysis. The addition product 16c was isolated by preparative column chromatography
(packing material; silica, eluent; CH2Cl2/n-hexan (5/2; v/v)).
Isolated yield of 16c: 80 mg (21 %), diastereomeric mixture, light yellow oil.
16c
1516
17
1213
1411
18 19
2
6
20
10
9
4
25
58
21
24
7
3
NH
CH
Cl
1
23
22
26
27
IR (CH2Cl2, CaF2) cm-1: 3482 (NH), 2980, 2926 (CH), 1451 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 0.92 (s, 3H, H26), 1.08-1.10 (m, 2H, H24), 1.12-
1.17 (m, 3H, H3,5,8), 1.20-1.27 (m, 6H, H4,9,10, s, 3H, H27), 1.47-1.52 (br, 6H, H2,6,7),
1.67 (s, 3H, H25), 2.06-2.14 (br, 1H, H21), 2.17-2.34 (br, 1H, H23), 3.61-3.64 (d, 1H,
H18I), 3.67-3.69 (d, 1H, H18II), 3.73 (s, 1H, H11), 4.41 (br, 1H, N-H), 5.32-5.49 (d, 1H,
H19I/II), 7.04-7.28 (m, aromatic protons). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 21.7 (C25), 25.2 (C26,27), 29.4 (C3), 29.5 (C5,8),
36.4 (C24), 36.5 (C4,9,10), 38.6 (C22), 43.4 (C1), 43.6 (C2,6,7), 43.8 (C18,23), 51.3
(C21), 58.4 (C11), 128.0 (C19I/II), 128.2 (C14,16), 129.1 (C13,17), 129.7 (C20I/II), 131.5
(C15), 132.4 (C12).
Elemental Analysis: C27H36ClN (410,03) Calculated: C 79.09; H 8.85; N 3.42 Found: no reproducible values could be handled
MS (FD, 2kV, in CH2Cl2, m/z): 410 [M+], 275 [M+-135]
Chapter 6. Experimental 183
6.5.2.3. Influence of p-Substituent
6.5.2.3.1.Addition reactions of cyclohexene to N-Adamantyl-p-X-benzaldehyde imine
derivatives (X: -H, -F, -Cl, -Br, -OCH3)
+30%CdS/Al2O3 hνMeOH/CH2Cl2
Ad:
Ar: X
N
Ad Ar
HHN
Ad Ar
H +HN
Ad Ar
HN
Ad Ar
9-13 b 14-18b 20,21
X -H -F -Cl -Br -OCH3 9 10 11 12 13
Addition 14b 15b 16b 17b 18bProduct
Hydrodimer - - 20 21 -
6.5.2.3.1.1.Addition of cyclohexene to N-Adamantyl-benzaldehyde imine
Analogous to 6.5.2.2.2 but using 9 (250 mg, 1.04 mmol). The suspension was irradiated
until complete consumption of 16 (3 d). The reaction progress was followed by analytical
HPLC (Eluent: CH3CN/CH2Cl2 (90/10; v/v), flow-rate: 0.5 ml/min) and TLC analysis. The
addition product 14b was isolated by preparative column chromatography (packing
material; silica, eluent; CH2Cl2/n-hexan=5/1 (v/v)). No hydrodimer of 9 was observed.
Chapter 6. Experimental 184
14b
1516
17
1213
1411
18 23
2
6
22
10
9
4
21
58
20
19
7
3
NH
CH1
Isolated yield of 14b: 200 mg (59 %), diastereomeric mixture, light yellow oil.
IR (CH2Cl2, CaF2) cm-1: 3482 (NH), 3050 (CHAr), 2930, 2852 (CH), 1450, 1601 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 1.15 (m, 2H, H22), 1.18-1.24 (m, 2H, H23), 1.41-
1.76 (m, 6H, H10,4,9), 1.78-2.02 (m, 6H, H2,6,7), 2.27-2.38 (m, 5H, H21,8,5,3), 2.53 (m,
1H, H18), 4.13 (br, 5H, H11,N-H), 5.66-5.72 (m, 1H, H20), 5.93-5.98 (m, 1H, H19), 6.89-
6.96 (m, 1H, H15), 7.12-7.22 (m, 2H, H17,13), 7.26-7.32 (m, 2H, H16,14). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 18.8 (C22), 22.4 (C8,5,3), 24.8 (C23), 26.8
(C10,4,9), 29.8 (C21), 35.0 (C1), 37.8 (C2,6,7), 44.3 (C18), 65.1 (C11), 127.3 (C15), 127.5
(C20), 127.6 (C16,14), 129.6 (C19), 129.9 (C17,13), 150.6 (C12).
Elemental Analysis: C23H31N (321,5) Calculated: C 85.92; H 9.72; N 4.36 Found : C 86.09; H 10.70; N 4.40
MS (FD, 2kV, in CHCl3, m/z): 323 [M++1], 241 [M+-82]
6.5.2.3.1.2. Addition of cyclohexene to N-Adamantyl-p-fluoro-benzaldehyde imine
Analogous to 6.5.2.2.2 but using 10 (250 mg, 0.97 mmol). The suspension was irradiated
until complete consumption of 10 (4 d). The reaction progress was followed by analytical
HPLC (Eluent: CH3CN/CH2Cl2 (90/10; v/v), flow-rate: 0.5 ml/min) and TLC analysis. The
addition product 15b was isolated by preparative column chromatography (packing
material; silica, eluent; CH2Cl2/n-hexan=5/2 (v/v)). No hydrodimer of 10 was observed.
Chapter 6. Experimental 185
15b
1516
17
1213
1411
18 23
2
6
22
10
9
4
21
58
20
19
7
3
NH
CH
F
1
Isolated yield of 15b: 270 mg (82 %), diastereomeric mixture, light yellow oil.
IR (CH2Cl2, CaF2) cm-1: 3675 (NH), 2922, 2851 (CH), 1505, 1602 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 0.81-0.82 (m, 2H, H22), 0.96-1.00 (m, 2H, H23),
1.39-1.53 (m, 12H, H2,6,7,10,4,9), 1.64-1.82 (m, 2H, H21), 1.89 (br, 3H, H8,5,3), 2.13-
2.14 (m, 1H, H18), 3.77-3.85 (d, 1H, H11), 4.12 (s, 1H, N-H), 5.65-5.69 (m, 1H, H20),
5.73-5.76 (m, 1H, H19), 6.85-7.26 (m, 4H, aromatic). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 20.6 (C22), 23.4 (C23), 29.5 (C21,8,5,3), 36.5
(C10,4,9), 43.3 (C1), 43.9 (C2,6,7), 51.2 (C11I), 52.8 (C18I), 57.2 (C11II), 53.6 (C18II),
114.5 (C16,14), 114.9 (C20), 128.5 (C17,13), 128.6 (C19), 129.0 (C12), 142.9 (C15).
Elemental Analysis: C23H30FN (339,49) Calculated: C 81.37; H 8.91; N 4.13 Found : C 80.09; H 9.29; N 3.11
MS (FD, 2kV, in CHCl3, m/z): 259 [M+-81]
6.5.2.3.1.3.Addition of cyclohexene to N-Adamantyl-p-chloro-benzaldehyde imine
See 6.5.2.2.2.
6.5.2.3.1.4. Addition of cyclohexene to N-Adamantyl-p-bromo-benzaldehyde imine
Analogous to 6.5.2.2.2 but using 12 (250 mg, 0.78 mmol). The suspension was irradiated
until complete consumption of 12 (4 d). The reaction progress was followed by analytical
HPLC (Eluent: CH3CN/CH2Cl2 (90/10; v/v), flow-rate: 0.5 ml/min) and TLC analysis. The
addition product 17b was isolated by preparative column chromatography (packing
material; silica, eluent; CH2Cl2/n-hexan=2/1 (v/v)). Traces of hydrodimer of 12 were
detected by HPLC but couldn’t be isolated from column chromatography.
Chapter 6. Experimental 186
17b
1516
17
1213
1411
18 23
2
6
22
10
9
4
21
58
20
19
7
3
NH
CH
Br
1
Isolated yield of 17b: 250 mg (79 %), diastereomeric mixture, light yellow oil.
IR (CH2Cl2, CaF2) cm-1: 3566 (NH), 2907, 2849 (CH), 1481, 1457 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 0.77-0.79 (m, 2H, H22), 1.08 (br, 2H, H23), 1.23
(2H, m, H21), 1.39-1.42 (m, 6H, H2,6,7), 1.42-1.54 (m, 6H, 10,4,9), 1.75-1.79 (m, 1H,
H18), 1.80-1.90 (m, 3H, 8,5,3), 4.14 (br, 2H, H11,N-H), 5.61-5.79 (m, 2H, H20,19), 7.17-
7.22 (m, 2H, H17,13) 7.33-7.38 (m, 2H, 16,14). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 14.1 (C22), 18.6 (C23), 18.9 (C8,5,3), 24.9
(C10,4,9), 29.5 (C21), 31.9 (C2,6,7), 35.5 (C1), 36.6 (C18), 65.4 (C11), 128.2 (C20), 129.4
(C15), 129.8 (C17,13,19), 130.5 (C16,14), 131.2 (C12).
Elemental Analysis: C23H30BrN (400,4) Calculated: C 68.99; H 7.55; N 3.50
Found : C 68.79; H 7.64; N 3.27
MS (FD, 2kV, in CHCl3, m/z): 319 [M+-81]
6.5.2.3.1.5. Addition of cyclohexene to N-Adamantyl-p-methoxy-benzaldehyde imine
Analogous to 6.5.2.2.2 but using 13 (250 mg, 0.93 mmol). The suspension was irradiated
until complete consumption of 13 (4 d). The reaction progress was followed by analytical
HPLC (Eluent: CH3CN/CH2Cl2 (90/10; v/v), flow-rate: 0.5 ml/min) and TLC analysis. The
addition product 18b was isolated by preparative column chromatography (packing
material; silica, eluent; CH2Cl2/n-hexan=5/1 (v/v)). No hydrodimer of 13 was observed.
Chapter 6. Experimental 187
18b
1516
17
1213
1411
18 23
2
6
22
10
9
4
21
58
20
19
7
3
NH
CH
O
1
CH324
Isolated yield of 18b: 155 mg (47 %), diastereomeric mixture, light yellow oil.
IR (CH2Cl2, CaF2) cm-1: 3511 (NH), 3029 (CHAr), 2935, 2865 (CH), 1452, 1437 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 0.75-0.83 (m, 2H, H22), 1.14-1.22 (m, 2H, H23),
1.63-1.69 (m, 12H, H2,6,7,10,4,9), 1.89-1.98 (m, 5H, H21,8,5,3), 2.03-2.04 (m, 1H, H18),
4.45 (br, 5H, H11,N-H,24), 5.68-5.69 (m, 1H, H20), 5.89-5.94 (m, 1H, H19), 7.20-7.26 (m,
4H, aromatic). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 14.0 (C22), 18.2 (C8,5,3), 18.3 (C23), 22.2 (C21),
25.3 (C1,10,4,9), 26.8 (C2,6,7), 29.6 (C18I), 34.1 (C18II), 75.9 (C24), 76.5 (C11), 123.9
(C16,14), 124.4 (C20), 133.8 (C19), 133.9 (C17,13,12), 140.7 (C15).
Elemental Analysis: C24H33ON (351,52) Calculated: C 82.00; H 9.46; N 3.98
Found: no reproducible values could be handled
MS (FD, 2kV, in CHCl3, m/z): 271 [M+-81]
Chapter 6. Experimental 188
6.5.2.3.2. Addition reactions of α-pinene to N-Adamantyl-p-X-benzaldehyde imine
derivatives (X: -H, -F, -Cl, -Br, -OCH3)
Ad:
Ar: X
X -H -F -Cl -Br -OCH3 9 10 11 12 13
Addition 14c 15c 16c 17c 18cProduct
Hydrodimer - 19 20 21 22
+
30%CdS/Al2O3 hν
MeOH/CH2Cl2N
Ad Ar
HHN
Ad Ar
H +HN
Ad Ar
HN
Ad Ar
9-16 c 14-18c 19-22
Me
6.5.2.3.2.1.Addition of α-pinene to N-Adamantyl-benzaldehyde imine
Analogous to 6.5.2.2.3 but using 9 (250 mg, 1.04 mmol). The suspension was irradiated
until complete consumption of 9 (3 d). The reaction progress was followed by analytical
HPLC (Eluent: CH3CN/CH2Cl2 =90/10 (v/v), flow-rate: 0.5 ml/min) and TLC analysis.
The addition product 14c was isolated by preparative column chromatography (packing
material; silica, eluent: ethyl acetate).
14c
1516
17
1213
1411
18 19
2
6
20
10
9
4
25
58
21
24
7
3
NH
CH1
2322
26
27
Chapter 6. Experimental 189
Isolated yield of 14c: 280 mg (71 %), diastereomeric mixture, white powder.
IR (CH2Cl2, CaF2) cm-1: 3479 (NH), 2920 (CH), 1446, 1468 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 0.72 (s, 3H, H26), 0.85-0.96 (m, 2H, H24), 1.01-
1.13 (m, 3H, H3,5,8), 1.16-1.25 (m, 6H, H4,9,10, s, 3H, H27), 1.45 (br, 6H, H2,6,7), 1.61
(s, 3H, H25), 1.84-1.87 (br, 1H, H21), 2.06-2.11 (br, 1H, H23), 3.54-3.57 (d, 1H, H18I),
3.63-3.66 (d, 1H, H18II), 3.73 (s, 1H, H11), 4.37 (br, 1H, N-H), 5.04-5.21 (d, 1H,
H19I/II), 7.08-7.31 (m, aromatic protons). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 20.4 (C25), 23.1 (C26,27), 26.4 (C3), 27.6 (C5,8),
29.4 (C24), 29.6 (C4,9,10), 36.6 (C22I/II), 40.5 (C2,6,7), 41.0 (C1), 42.4 (C18I), 43.0
(C18II), 44.1 (C23), 47.4 (C21), 58.2 (C11), 118.5 (C19I), 119.1 (C19II), 119.6 (C15),
127.2 (C13,17), 127.7 (C20I/II), 127.8 (C14,16), 144.2 (C12).
Elemental Analysis: C27H37N (375,6) Calculated: C 86.34; H 9.93; N 3.73
Found : C 86.49; H 10.30; N 3.40
MS (FD, 2kV, in CH2Cl2, m/z): 376 [M+], 241 [M+-135]
6.5.2.3.2.2. Addition of α-pinene to N-Adamantyl-p-fluoro-benzaldehyde imine
Analogous to 6.5.2.2.3 but using 10 (250 mg, 0.97 mmol). The suspension was irradiated
until complete consumption of 10 (4 d). The reaction progress was followed by analytical
HPLC (Eluent: CH3CN/CH2Cl2=90/10 (v/v), flow-rate: 0.5 ml/min) and TLC analysis. The
addition product 15c was isolated by preparative column chromatography (packing
material; silica, eluent: ethyl acetate).
15c
1516
17
1213
1411
18 19
2
6
20
10
9
4
25
58
21
24
7
3
NH
CH
F
1
2322
26
27
Chapter 6. Experimental 190
Isolated yield of 15c: 310 mg (81 %), diastereomeric mixture, light yellow oil.
IR (CH2Cl2, CaF2) cm-1: 3566 (NH), 2983, 2917, 2848 (CH), 1447, 1506, 1601 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 0.71 (s, 3H, H26), 0.84-0.92 (m, 2H, H24), 1.04-
1.10 (m, 3H, H3,5,8), 1.15-1.26 (m, 6H, H4,9,10, s, 3H, H27), 1.46-1.47 (br, 6H, H2,6,7),
1.60 (s, 3H, H25), 1.84-1.87 (br, 1H, H21), 2.06-2.11 (br, 1H, H23), 3.56-3.62 (d, 1H,
H18I), 3.65-3.71 (d, 1H, H18II), 3.76 (s, 1H, H11), 4.36 (br, 1H, N-H), 5.14-5.31 (d, 1H,
H19I/II), 6.84-7.21 (m, aromatic protons). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 20.3 (C25), 23.0 (C26,27), 26.5 (C3), 27.6 (C5,8),
29.4 (C24), 29.6 (C4,9,10), 36.6 (C22), 40.4 (C2,6,7), 41.0 (C1), 42.4 (C18I), 43.1 (C18II),
43.8 (C23), 47.4 (C21), 57.5 (C11), 118.5 (C19I), 118.8 (C19II), 119.6 (C14,16), 128.5
(C20I), 128.9 (C13,17), 129.6 (C20II), 144.2 (C12) , 163.1 (C15).
Elemental Analysis: C27H36FN (393,6) Calculated: C 82.39; H 9.22; N 3.56
Found : C 82.39; H 10.00; N 3.31
MS (FD, 2kV, in CH2Cl2, m/z): 394 [M+], 259 [M+-135]
6.5.2.3.2.3.Addition of α-pinene to N-Adamantyl-p-chloro-benzaldehyde imine
See 6.5.2.2.3.
6.5.2.3.2.4. Addition of α-pinene to N-Adamantyl-p-bromo-benzaldehyde imine
Analogous to 6.5.2.2.5 but using 12 (250 mg, 0.78 mmol). The suspension was irradiated
until complete consumption of 12 (4 d). The reaction progress was followed by analytical
HPLC (Eluent: CH3CN/CH2Cl2=90/10 (v/v), flow-rate: 0.5 ml/min) and TLC analysis.
The addition product 17c was isolated by preparative column chromatography (packing
material; silica, eluent: ethyl acetate).
Chapter 6. Experimental 191
17c
1516
17
1213
1411
18 19
2
6
20
10
9
4
25
58
21
24
7
3
NH
CH
Br
1
23
22
26
27
Isolated yield of 17c: 305 mg (85 %), diastereomeric mixture, white powder.
IR (CH2Cl2, CaF2) cm-1: 3610 (NH), 3055 (CHAr), 2984, 2917 (CH), 1456, 1558 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 0.78 (s, 3H, H26), 0.90-0.97 (m, 2H, H24), 1.08-
1.18 (m, 3H, H3,5,8), 1.22-1.30 (m, 6H, H4,9,10, s, 3H, H27), 1.49-1.53 (br, 6H, H2,6,7),
1.65 (s, 3H, H25), 1.92-1.98 (br, 1H, H21), 2.08-2.14 (br, 1H, H23), 3.60-3.77 (d, 1H,
H18I/II), 3.77 (s, 1H, H11), 4.42 (br, 1H, N-H), 5.20-5.44 (d, 1H, H19I/II), 7.08-7.36 (m,
aromatic protons). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 20.3 (C25), 23.1 (C26,27), 26.5 (C3), 27.6 (C5,8),
29.5 (C4,9,10), 29.7 (C24), 36.4 (C22I), 36.6 (C22II), 40.5 (C2,6,7), 41.0 (C1), 42.8
(C18I), 43.1 (C18II), 43.7 (C23I), 43.9 (C23II), 47.1 (C21), 60.7 (C11), 118.5 (C19I),
118.9 (C19II), 119.6 (C15), 129.2 (C20I), 129.6 (C20II), 130.0 (C13,17), 130.7 (C14,16),
144.4 (C12).
Elemental Analysis: C27H36BrN (454,5) Calculated: C 71.35; H 7.98; N 3.08
Found: no reproducible values could be handled
MS (FD, 2kV, in CH2Cl2, m/z): 455 [M+], 319 [M+-135]
6.5.2.3.2.5. Addition of α-pinene to N-Adamantyl-p-methoxy-benzaldehyde imine
Analogous to 6.5.2.2.3 but using 13 (250 mg, 0.93 mmol). The suspension was irradiated
until complete consumption of 13 (4 d). The reaction progress was followed by analytical
HPLC (Eluent: CH3CN/CH2Cl2 =90/10 (v/v), flow-rate: 0.5 ml/min) and TLC analysis.
The addition product 18c was isolated by preparative column chromatography (packing
material; silica, eluent: ethyl acetate).
Chapter 6. Experimental 192
18c
1516
17
1213
1411
18 19
2
6
20
10
9
4
25
58
21
24
7
3
NH
CH
O
1
2322
26
27
CH328
Isolated yield of 18c: 230 mg (61 %), diastereomeric mixture, yellow oil.
IR (CH2Cl2, CaF2) cm-1: 3602 (NH), 2919 (CH), 1446, 1508, 1605 (C=C). 1H-NMR (270 MHz, CDCl3): δ (ppm) = 0.71 (s, 3H, H26), 0.89-0.92 (m, 2H, H24), 1.04-
1.09 (m, 3H, H3,5,8), 1.16-1.27 (m, 6H, H4,9,10, s, 3H, H27), 1.47 (br, 6H, H2,6,7), 1.59
(s, 3H, H25), 1.84-1.92 (br, 1H, H21), 2.05-2.08 (br, 1H, H23), 3.59-3.66 (d, 1H, H18I/II),
3.71 (s, 1H, H11), 3.80 (s, 3H, H28) 4.39 (br, 1H, N-H), 5.14-5.32 (d, 1H, H19I/II), 6.70-
7.21 (m, aromatic protons). 13C-NMR (270 MHz, CDCl3): δ (ppm) = 20.3 (C25), 23.0 (C26,27), 26.3 (C3), 27.7 (C5,8),
29.3 (C24), 29.9 (C4,9,10), 36.5 (C22), 40.4 (C2,6,7), 40.9 (C1), 42.7 (C18I), 43.0 (C18II),
43.9 (C23), 47.3 (C21), 54.9 (C11), 55.4 (C28), 113.1 (C14,16), 118.4 (C19I/II), 128.1
(C20I), 128.5 (C13,17), 131.8 (C20II), 144.2 (C12), 157.8 (C15).
Elemental Analysis: C28H39NO (405,6) Calculated: C 82.91; H 9.69; N 3.45
Found: no reproducible values could be handled
MS (FD, 2kV, in CH2Cl2, m/z): 406 [M+], 271 [M+-135]
Chapter 6. Experimental 193
6.6. Crystal Structure Determinations
All structural data were collected on a Bruker-Nonius Kappa CCD diffractometer using
MoKα irradiation (graphite monochromator, λ=0.71073 A°) at a temperature of 100K.
All structures were solved by direct methods and refined using full-matrix least-squares
procedures on F2 (SHELXTL 6.12).
All non-hydrogen atoms have been refined anisotropically and the positions of all hydrogen
atoms were located in a difference fourier syntheses.
Chapter 6. Experimental 194
6.6.1. Crystal data and structure refinement for N-Adamantyl-benzaldehyde imine
Empirical formula C17H21N
Formula weight 239.35
Temperature 100(2) K
Wavelength 0.71073 A°
Crystal system, space group Orthorhombic, P2(1)2(1)2(1)
Unit cell dimensions a = 6.4052(4) A° alpha = 90°
b = 7.0492(5) A° beta = 90°
c = 29.396(2) A° gamma = 90°
Volume 1327.3(3) A°3
Z, Calculated density 4, 1.198 Mg/m3
Absorption coefficient 0.069 mm-1
F(000) 520
Crystal size 0.32 x 0.23 x 0.22 mm
Theta range for data collection 2.97 to 27.10°
Limiting indices -8 ≤ h ≤ 8, -8 ≤ k ≤ 8, -37 ≤ l ≤ 37
Reflections collected / unique 10438 / 2689 [R(int) = 0.0560]
Completeness to theta = 27.10 96.8 %
Absorption correction Integration
Max. and min. transmission 0.987 and 0.982
Refinement method Full-matrix least-squares on F2
Data / restraints / parameters 2689 / 0 / 227
Goodness-of-fit on F2 1.053
Final R indices [I>2sigma(I)] R1 = 0.0438, wR2 = 0.0880
R indices (all data) R1 = 0.0589, wR2 = 0.0930
Absolute structure parameter 0(4)
Largest diff. peak and hole 0.187 and -0.240 e.A°-3
Chapter 6. Experimental 195
______________________________________ __________________________
x y z U(eq)
_________________ _______________________________________________
N(1) 1547(2) 9383(2) 1105(1) 16(1)
C(1) 1849(2) 10916(2) 1439(1) 14(1)
C(2) 3840(3) 10444(2) 1710(1) 17(1)
C(3) 4392(3) 12099(2) 2029(1) 16(1)
C(4) 4745(3) 13905(2) 1749(1) 17(1)
C(5) 2761(2) 14394(2) 1482(1) 15(1)
C(6) 2226(3) 12738(2) 1164(1) 15(1)
C(7) 52(3) 11261(2) 1774(1) 13(1)
C(8) 607(3) 12910(2) 2097(1) 14(1)
C(9) 961(3) 14720(2) 1817(1) 16(1)
C(10) 2591(3) 12415(2) 2362(1) 17(1)
C(11) -220(3) 8588(2) 1065(1) 16(1)
C(12) -641(3) 7108(2) 722(1) 15(1)
C(13) 850(3) 6565(2) 401(1) 18(1)
C(14) 372(3) 5181(2) 81(1) 20(1)
C(15) -1576(3) 4329(2) 81(1) 23(1)
C(16) -3061(3) 4858(2) 398(1) 23(1)
C(17) -2604(3) 6239(2) 717(1) 19(1)
____________________________________ ____________________________
Table 6.17: Atomic coordinates ( x 104) and equivalent isotropic displacement parameters
(A2 x 103) for N-Adamantyl-benzaldehyde imine. U(eq) is defined as one third of the trace
of the orthogonalized Uij tensor.
Chapter 6. Experimental 196
Table 6.18: Bond lengths [A] and angles [°] for N-Adamantyl-benzaldehyde imine.
N(1)-C(11) 1.269(2)
N(1)-C(1) 1.4736(19)
C(1)-C(7) 1.534(2)
C(1)-C(6) 1.537(2)
C(1)-C(2) 1.539(2)
C(2)-C(3) 1.539(2)
C(2)-H(2A) 0.990(18)
C(2)-H(2B) 1.003(18)
C(3)-C(10) 1.529(2)
C(3)-C(4) 1.533(2)
C(3)-H(3) 1.020(19)
C(4)-C(5) 1.533(2)
C(4)-H(4A) 1.039(18)
C(4)-H(4B) 0.964(19)
C(5)-C(6) 1.533(2)
C(5)-C(9) 1.534(2)
C(5)-H(5) 1.018(18)
C(6)-H(6A) 0.984(18)
C(6)-H(6B) 1.019(19)
C(7)-C(8) 1.542(2)
C(7)-H(7A) 1.029(18)
C(7)-H(7B) 1.007(19)
C(8)-C(10) 1.532(2)
C(8)-C(9) 1.535(2)
C(8)-H(8) 0.990(19)
C(9)-H(9A) 1.035(19)
C(9)-H(9B) 0.991(19)
C(10)-H(10A) 1.026(18)
C(10)-H(10B) 1.005(19)
C(11)-C(12) 1.476(2)
C(11)-H(11) 1.011(18)
C(12)-C(13) 1.397(2)
C(12)-C(17) 1.398(2)
C(13)-C(14) 1.389(2)
C(13)-H(13) 1.008(19)
C(14)-C(15) 1.385(3)
C(14)-H(14) 1.011(18)
C(15)-C(16) 1.382(2)
C(15)-H(15) 0.937(17)
C(16)-C(17) 1.383(2)
C(16)-H(16) 0.999(19)
C(17)-H(17) 0.968(19)
C(11)-N(1)-C(1) 120.14(13)
N(1)-C(1)-C(7) 116.47(13)
N(1)-C(1)-C(6) 106.42(11)
C(7)-C(1)-C(6) 108.83(13)
N(1)-C(1)-C(2) 107.14(13)
C(7)-C(1)-C(2) 108.97(13)
C(6)-C(1)-C(2) 108.80(13)
C(3)-C(2)-C(1) 109.97(14)
C(3)-C(2)-H(2A) 112.0(10)
C(1)-C(2)-H(2A) 107.2(11)
Chapter 6. Experimental 197
C(3)-C(2)-H(2B) 111.7(10)
C(1)-C(2)-H(2B) 109.2(10)
H(2A)-C(2)-H(2B) 106.6(14)
C(10)-C(3)-C(4) 109.50(14)
C(10)-C(3)-C(2) 109.17(14)
C(4)-C(3)-C(2) 109.63(13)
C(10)-C(3)-H(3) 110.4(10)
C(4)-C(3)-H(3) 109.8(10)
C(2)-C(3)-H(3) 108.3(11)
C(3)-C(4)-C(5) 109.88(13)
C(3)-C(4)-H(4A) 108.2(9)
C(5)-C(4)-H(4A) 111.7(10)
C(3)-C(4)-H(4B) 111.8(11)
C(5)-C(4)-H(4B) 110.2(10)
H(4A)-C(4)-H(4B) 104.9(15)
C(6)-C(5)-C(4) 109.04(14)
C(6)-C(5)-C(9) 109.66(14)
C(4)-C(5)-C(9) 109.11(13)
C(6)-C(5)-H(5) 109.6(9)
C(4)-C(5)-H(5) 109.0(10)
C(9)-C(5)-H(5) 110.5(10)
C(5)-C(6)-C(1) 110.58(12)
C(5)-C(6)-H(6A) 109.8(11)
C(1)-C(6)-H(6A) 109.1(11)
C(5)-C(6)-H(6B) 109.2(10)
C(1)-C(6)-H(6B) 108.9(10)
H(6A)-C(6)-H(6B) 109.3(13)
C(1)-C(7)-C(8) 109.92(13)
C(1)-C(7)-H(7A) 109.7(10)
C(8)-C(7)-H(7A) 109.8(9)
C(1)-C(7)-H(7B) 110.0(10)
C(8)-C(7)-H(7B) 111.7(10)
H(7A)-C(7)-H(7B) 105.6(15)
C(10)-C(8)-C(9) 109.89(14)
C(10)-C(8)-C(7) 109.46(14)
C(9)-C(8)-C(7) 109.34(13)
C(10)-C(8)-H(8) 109.7(10)
C(9)-C(8)-H(8) 108.4(11)
C(7)-C(8)-H(8) 110.1(11)
C(5)-C(9)-C(8) 109.31(14)
C(5)-C(9)-H(9A) 108.2(10)
C(8)-C(9)-H(9A) 112.6(9)
C(5)-C(9)-H(9B) 111.6(10)
C(8)-C(9)-H(9B) 111.4(11)
H(9A)-C(9)-H(9B) 103.6(14)
C(3)-C(10)-C(8) 109.40(12)
C(3)-C(10)-H(10A) 109.9(11)
C(8)-C(10)-H(10A) 109.6(11)
C(3)-C(10)-H(10B) 109.2(11)
C(8)-C(10)-H(10B) 108.3(11)
H(10A)-C(10)-H(10B) 110.4(13)
N(1)-C(11)-C(12) 122.54(15)
N(1)-C(11)-H(11) 122.9(9)
C(12)-C(11)-H(11) 114.5(9)
C(13)-C(12)-C(17) 119.15(15)
C(13)-C(12)-C(11) 122.08(15)
Chapter 6. Experimental 198
C(17)-C(12)-C(11) 118.77(14)
C(14)-C(13)-C(12) 119.98(16)
C(14)-C(13)-H(13) 118.3(11)
C(12)-C(13)-H(13) 121.7(11)
C(15)-C(14)-C(13) 120.17(16)
C(15)-C(14)-H(14) 122.2(10)
C(13)-C(14)-H(14) 117.5(10)
C(16)-C(15)-C(14) 120.23(16)
C(16)-C(15)-H(15) 118.4(11)
C(14)-C(15)-H(15) 121.3(11)
C(15)-C(16)-C(17) 120.06(17)
C(15)-C(16)-H(16) 120.7(10)
C(17)-C(16)-H(16) 119.2(10)
C(16)-C(17)-C(12) 120.42(16)
C(16)-C(17)-H(17) 122.5(11)
C(12)-C(17)-H(17) 116.9(11)
Chapter 6. Experimental 199
Table 6.19: Torsion angles [°] for N-Adamantyl-benzaldehyde imine.
C(11)-N(1)-C(1)-C(7) 8.9(2)
C(11)-N(1)-C(1)-C(6) -112.60(16)
C(11)-N(1)-C(1)-C(2) 131.14(16)
N(1)-C(1)-C(2)-C(3) 173.63(12)
C(7)-C(1)-C(2)-C(3) -59.56(17)
C(6)-C(1)-C(2)-C(3) 58.96(17)
C(1)-C(2)-C(3)-C(10) 60.45(17)
C(1)-C(2)-C(3)-C(4) -59.49(18)
C(10)-C(3)-C(4)-C(5) -60.05(17)
C(2)-C(3)-C(4)-C(5) 59.70(18)
C(3)-C(4)-C(5)-C(6) -59.61(16)
C(3)-C(4)-C(5)-C(9) 60.13(18)
C(4)-C(5)-C(6)-C(1) 60.01(17)
C(9)-C(5)-C(6)-C(1) -59.40(17)
N(1)-C(1)-C(6)-C(5) -174.75(13)
C(7)-C(1)-C(6)-C(5) 59.00(17)
C(2)-C(1)-C(6)-C(5) -59.61(17)
N(1)-C(1)-C(7)-C(8) -179.62(12)
C(6)-C(1)-C(7)-C(8) -59.39(16)
C(2)-C(1)-C(7)-C(8) 59.11(18)
C(1)-C(7)-C(8)-C(10) -59.85(16)
C(1)-C(7)-C(8)-C(9) 60.58(18)
C(6)-C(5)-C(9)-C(8) 59.51(17)
C(4)-C(5)-C(9)-C(8) -59.86(18)
C(10)-C(8)-C(9)-C(5) 60.06(17)
C(7)-C(8)-C(9)-C(5) -60.11(18)
C(4)-C(3)-C(10)-C(8) 59.48(17)
C(2)-C(3)-C(10)-C(8) -60.55(18)
C(9)-C(8)-C(10)-C(3) -59.80(18)
C(7)-C(8)-C(10)-C(3) 60.30(17)
C(1)-N(1)-C(11)-C(12) 177.09(13)
N(1)-C(11)-C(12)-C(13) -3.8(2)
N(1)-C(11)-C(12)-C(17) 176.82(15)
C(17)-C(12)-C(13)-C(14) 0.1(2)
C(11)-C(12)-C(13)-C(14) -179.22(14)
C(12)-C(13)-C(14)-C(15) -0.4(2)
C(13)-C(14)-C(15)-C(16) 0.3(2)
C(14)-C(15)-C(16)-C(17) -0.1(3)
C(15)-C(16)-C(17)-C(12) -0.1(3)
C(13)-C(12)-C(17)-C(16) 0.1(2)
C(11)-C(12)-C(17)-C(16) 179.48(16)
Chapter 6. Experimental 200
6.6.2. Crystal data and structure refinement for N-Adamantyl-p-fluoro-
benzaldehyde imine
Empirical formula C17H20FN
Formula weight 257.34
Temperature 100(2) K
Wavelength 0.71073 A
Crystal system, space group Monoclinic, P21/c
Unit cell dimensions a = 6.4759(5) A° alpha = 90°
b = 33.280(2) A° beta = 116.291(6)°
c = 6.8092(3) A° gamma = 90°
Volume 1315.7(2) A3
Z, Calculated density 4, 1.299 Mg/m3
Absorption coefficient 0.085 mm-1
F(000) 552
Crystal size 0.25 x 0.22 x 0.08 mm
Theta range for data collection 3.96 to 26.37°
Limiting indices -8 ≤ h ≤ 8, -41 ≤ k ≤ 41, -8 ≤ l ≤ 8
Reflections collected / unique 21697 / 2630 [R(int) = 0.1045]
Completeness to theta = 26.37 97.8 %
Absorption correction Integration
Max. and min. transmission 0.993 and 0.974
Refinement method Full-matrix least-squares on F2
Data / restraints / parameters 2630 / 0 / 232
Goodness-of-fit on F2 R1 = 0.0503, wR2 = 0.1027
R indices (all data) R1 = 0.0770, wR2 = 0.1117
Largest diff. peak and hole 0.242 and -0.208 e.A°-3
Chapter 6. Experimental 201
_____________ ___________________________________________________
x y z U(eq)
__________________________________ ______________________________
F(1) 5456(2) 1493(1) 9488(2) 22(1)
N(1) 2508(2) 3333(1) 8293(2) 14(1)
C(1) 2297(3) 3774(1) 8288(3) 14(1)
C(2) 1102(3) 3911(1) 5885(3) 16(1)
C(3) 582(3) 4363(1) 5762(3) 17(1)
C(4) -1013(3) 4447(1) 6834(3) 19(1)
C(5) 175(3) 4317(1) 9243(3) 17(1)
C(6) 703(3) 3866(1) 9369(3) 16(1)
C(7) 4540(3) 4011(1) 9471(3) 16(1)
C(8) 4009(3) 4464(1) 9359(3) 18(1)
C(9) 2430(3) 4548(1) 10441(3) 19(1)
C(10) 2823(3) 4596(1) 6963(3) 19(1)
C(11) 4462(3) 3164(1) 9103(3) 14(1)
C(12) 4700(3) 2722(1) 9172(3) 13(1)
C(13) 2806(3) 2472(1) 8709(3) 14(1)
C(14) 3050(3) 2059(1) 8788(3) 15(1)
C(15) 5204(3) 1902(1) 9367(3) 15(1)
C(16) 7121(3) 2134(1) 9855(3) 16(1)
C(17) 6843(3) 2550(1) 9743(3) 15(1)
_______________________________________ _________________________
Table 6.8: Atomic coordinates ( x 104) and equivalent isotropic displacement parameters
(A2 x 103) for N-Adamantyl-p- fluoro-benzaldehyde imine. U(eq) is defined as one third of
the trace of the orthogonalized Uij tensor.
Chapter 6. Experimental 202
Table 6.9: Bond lengths [A] and angles [°] for N-Adamantyl-p- fluoro-benzaldehyde
imine.
F(1)-C(15) 1.3687(18)
N(1)-C(11) 1.265(2)
N(1)-C(1) 1.4721(19)
C(1)-C(7) 1.532(2)
C(1)-C(2) 1.538(2)
C(1)-C(6) 1.540(2)
C(2)-C(3) 1.537(2)
C(2)-H(2A) 0.98(2)
C(2)-H(2B) 1.01(2)
C(3)-C(10) 1.525(3)
C(3)-C(4) 1.532(2)
C(3)-H(3) 0.99(2)
C(4)-C(5) 1.533(2)
C(4)-H(4A) 1.00(2)
C(4)-H(4B) 0.99(2)
C(5)-C(9) 1.529(2)
C(5)-C(6) 1.534(2)
C(5)-H(5) 0.97(2)
C(6)-H(6A) 1.00(2)
C(6)-H(6B) 1.00(2)
C(7)-C(8) 1.540(2)
C(7)-H(7A) 1.00(2)
C(7)-H(7B) 1.01(2)
C(8)-C(10) 1.528(3)
C(8)-C(9) 1.528(3)
C(8)-H(8) 1.02(2)
C(9)-H(9A) 0.99(2)
C(9)-H(9B) 1.00(2)
C(10)-H(10A) 0.99(2)
C(10)-H(10B) 0.99(2)
C(11)-C(12) 1.480(2)
C(11)-H(11) 0.98(2)
C(12)-C(17) 1.388(2)
C(12)-C(13) 1.396(2)
C(13)-C(14) 1.384(2)
C(13)-H(13) 0.97(2)
C(14)-C(15) 1.373(2)
C(14)-H(14) 0.98(2)
C(15)-C(16) 1.371(2)
C(16)-C(17) 1.394(2)
C(16)-H(16) 0.97(2)
C(17)-H(17) 0.98(2)
C(11)-N(1)-C(1) 121.11(14)
N(1)-C(1)-C(7) 116.53(14)
N(1)-C(1)-C(2) 107.51(13)
C(7)-C(1)-C(2) 108.61(14)
N(1)-C(1)-C(6) 106.16(13)
C(7)-C(1)-C(6) 109.05(14)
C(2)-C(1)-C(6) 108.76(14)
C(3)-C(2)-C(1) 110.12(14)
C(3)-C(2)-H(2A) 110.7(11)
C(1)-C(2)-H(2A) 109.9(12)
Chapter 6. Experimental 203
C(3)-C(2)-H(2B) 110.3(11)
C(1)-C(2)-H(2B) 108.4(11)
H(2A)-C(2)-H(2B) 107.4(16)
C(10)-C(3)-C(4) 109.54(15)
C(10)-C(3)-C(2) 109.61(15)
C(4)-C(3)-C(2) 109.24(14)
C(10)-C(3)-H(3) 111.5(11)
C(4)-C(3)-H(3) 108.3(11)
C(2)-C(3)-H(3) 108.6(11)
C(3)-C(4)-C(5) 109.49(15)
C(3)-C(4)-H(4A) 112.3(11)
C(5)-C(4)-H(4A) 108.2(11)
C(3)-C(4)-H(4B) 110.6(11)
C(5)-C(4)-H(4B) 108.7(11)
H(4A)-C(4)-H(4B) 107.5(16)
C(9)-C(5)-C(4) 109.68(15)
C(9)-C(5)-C(6) 109.12(15)
C(4)-C(5)-C(6) 109.26(14)
C(9)-C(5)-H(5) 109.8(12)
C(4)-C(5)-H(5) 109.8(12)
C(6)-C(5)-H(5) 109.2(11)
C(5)-C(6)-C(1) 110.37(14)
C(5)-C(6)-H(6A) 110.2(11)
C(1)-C(6)-H(6A) 108.7(11)
C(5)-C(6)-H(6B) 109.6(11)
C(1)-C(6)-H(6B) 110.0(11)
H(6A)-C(6)-H(6B) 107.9(15)
C(1)-C(7)-C(8) 109.85(14)
C(1)-C(7)-H(7A) 109.6(11)
C(8)-C(7)-H(7A) 110.0(11)
C(1)-C(7)-H(7B) 110.1(11)
C(8)-C(7)-H(7B) 109.8(11)
H(7A)-C(7)-H(7B) 107.5(16)
C(10)-C(8)-C(9) 109.52(15)
C(10)-C(8)-C(7) 109.34(14)
C(9)-C(8)-C(7) 109.83(14)
C(10)-C(8)-H(8) 108.9(11)
C(9)-C(8)-H(8) 110.1(11)
C(7)-C(8)-H(8) 109.1(11)
C(8)-C(9)-C(5) 109.53(14)
C(8)-C(9)-H(9A) 110.7(12)
C(5)-C(9)-H(9A) 109.2(11)
C(8)-C(9)-H(9B) 110.3(11)
C(5)-C(9)-H(9B) 110.3(11)
H(9A)-C(9)-H(9B) 106.8(15)
C(3)-C(10)-C(8) 109.54(14)
C(3)-C(10)-H(10A) 110.2(11)
C(8)-C(10)-H(10A) 110.3(11)
C(3)-C(10)-H(10B) 110.3(11)
C(8)-C(10)-H(10B) 109.2(11)
H(10A)-C(10)-H(10B) 107.2(15)
N(1)-C(11)-C(12) 121.69(16)
Chapter 6. Experimental 204
N(1)-C(11)-H(11) 123.6(11)
C(12)-C(11)-H(11) 114.7(11)
C(17)-C(12)-C(13) 119.18(15)
C(17)-C(12)-C(11) 119.76(15)
C(13)-C(12)-C(11) 121.05(15)
C(14)-C(13)-C(12) 120.60(16)
C(14)-C(13)-H(13) 119.2(11)
C(12)-C(13)-H(13) 120.2(11)
C(15)-C(14)-C(13) 118.14(16)
C(15)-C(14)-H(14) 118.7(12)
C(13)-C(14)-H(14) 123.2(12)
F(1)-C(15)-C(16) 118.22(15)
F(1)-C(15)-C(14) 118.23(15)
C(16)-C(15)-C(14) 123.55(15)
C(15)-C(16)-C(17) 117.63(17)
C(15)-C(16)-H(16) 122.2(11)
C(17)-C(16)-H(16) 120.2(11)
C(12)-C(17)-C(16) 120.90(17)
C(12)-C(17)-H(17) 119.5(11)
C(16)-C(17)-H(17) 119.6(11)
Chapter 6. Experimental 205
Table 6.10: Torsion angles [°] for N-Adamantyl-p-fluoro-benzaldehyde imine.
C(11)-N(1)-C(1)-C(7) -4.8(2)
C(11)-N(1)-C(1)-C(2) 117.33(17)
C(11)-N(1)-C(1)-C(6) -126.41(16)
N(1)-C(1)-C(2)-C(3) 173.65(14)
C(7)-C(1)-C(2)-C(3) -59.45(18)
C(6)-C(1)-C(2)-C(3) 59.10(18)
C(1)-C(2)-C(3)-C(10) 59.74(19)
C(1)-C(2)-C(3)-C(4) -60.29(19)
C(10)-C(3)-C(4)-C(5) -59.61(18)
C(2)-C(3)-C(4)-C(5) 60.46(19)
C(3)-C(4)-C(5)-C(9) 59.33(18)
C(3)-C(4)-C(5)-C(6) -60.23(18)
C(9)-C(5)-C(6)-C(1) -60.04(19)
C(4)-C(5)-C(6)-C(1) 59.86(19)
N(1)-C(1)-C(6)-C(5) -174.43(14)
C(7)-C(1)-C(6)-C(5) 59.26(18)
C(2)-C(1)-C(6)-C(5) -59.01(18)
N(1)-C(1)-C(7)-C(8) -178.65(14)
C(2)-C(1)-C(7)-C(8) 59.83(18)
C(6)-C(1)-C(7)-C(8) -58.55(18)
C(1)-C(7)-C(8)-C(10) -60.59(19)
C(1)-C(7)-C(8)-C(9) 59.60(19)
C(10)-C(8)-C(9)-C(5) 59.93(18)
.C(7)-C(8)-C(9)-C(5) -60.16(19)
C(4)-C(5)-C(9)-C(8) -59.52(18)
C(6)-C(5)-C(9)-C(8) 60.12(19)
C(4)-C(3)-C(10)-C(8) 60.15(18)
C(2)-C(3)-C(10)-C(8) -59.70(18)
C(9)-C(8)-C(10)-C(3) -60.31(18)
C(7)-C(8)-C(10)-C(3) 60.08(19)
C(1)-N(1)-C(11)-C(12) 178.36(14)
N(1)-C(11)-C(12)-C(17) 169.62(16)
N(1)-C(11)-C(12)-C(13) -11.5(2)
C(17)-C(12)-C(13)-C(14) -0.8(2)
C(11)-C(12)-C(13)-C(14) -179.67(15)
C(12)-C(13)-C(14)-C(15) 1.0(2)
C(13)-C(14)-C(15)-F(1) 178.76(14)
C(13)-C(14)-C(15)-C(16) -0.4(3)
F(1)-C(15)-C(16)-C(17) -179.48(14)
C(14)-C(15)-C(16)-C(17) -0.3(3)
C(13)-C(12)-C(17)-C(16) 0.1(2)
C(11)-C(12)-C(17)-C(16) 178.94(15)
C(15)-C(16)-C(17)-C(12) 0.5(3)
Chapter 6. Experimental 206
6.6.3. Crystal data and structure refinement for N-Adamantyl-p-chloro-
benzaldehyde imine
Empirical formula C17H20ClN
Formula weight 273.79
Temperature 100(2) K
Wavelength 0.71073 A°
Crystal system, space group Monoclinic, C2/c
Unit cell dimensions a = 27.270(3) A° alpha = 90°
b = 6.4963(3) A° beta = 107.590(8) °
c = 16.418(2) A° gamma = 90°
Volume 2772.5(5) A°3
Z, Calculated density 8, 1.312 Mg/m3
Absorption coefficient 0.261 mm-1
F(000) 1168
Crystal size 0.35 x 0.20 x 0.18 mm
Theta range for data collection 3.90 to 27.88°
Limiting indices -35 ≤ h ≤ 35, -8 ≤ k ≤ 8, -21 ≤ l ≤ 21
Reflections collected / unique 34135 / 3304 [R(int) = 0.0264]
Completeness to theta = 27.88° 99.6 %
Absorption correction Semi-empirical from equivalents
Max. and min. transmission 1.000 and 0.944
Refinement method Full-matrix least-squares on F2
Data / restraints / parameters 3304 / 0 / 232
Goodness-of-fit on F2 1.064
Final R indices [I>2sigma(I)] R1 = 0.0317, wR2 = 0.0803
R indices (all data) R1 = 0.0395, wR2 = 0.0854
Largest diff. peak and hole 0.404 and -0.227 e.A°-3
Chapter 6. Experimental 207
___ _____________________________________________________________
x y z U(eq)
________________________ ________________________________________
Cl(1) 6370(1) 5437(1) 5399(1) 20(1)
N(1) 4233(1) 8876(2) 6236(1) 14(1)
C(1) 3760(1) 9198(2) 6480(1) 12(1)
C(2) 3839(1) 11208(2) 7003(1) 14(1)
C(3) 3345(1) 11777(2) 7220(1) 14(1)
C(4) 2904(1) 12078(2) 6385(1) 16(1)
C(5) 2817(1) 10072(2) 5866(1) 14(1)
C(6) 3312(1) 9504(2) 5651(1) 14(1)
C(7) 3617(1) 7467(2) 7004(1) 13(1)
C(8) 3123(1) 8031(2) 7222(1) 14(1)
C(9) 2679(1) 8335(2) 6393(1) 16(1)
C(10) 3206(1) 10031(2) 7743(1) 16(1)
C(11) 4481(1) 7199(2) 6427(1) 13(1)
C(12) 4954(1) 6799(2) 6188(1) 13(1)
C(13) 5192(1) 8361(2) 5857(1) 13(1)
C(14) 5623(1) 7952(2) 5600(1) 14(1)
C(15) 5820(1) 5958(2) 5694(1) 14(1)
C(16) 5595(1) 4381(2) 6025(1) 15(1)
C(17) 5160(1) 4816(2) 6273(1) 15(1)
_______________________________________________ _________________
Table 6.5: Atomic coordinates ( x 104) and equivalent isotropic displacement parameters
(A2 x 103) for N-Adamantyl-p-chloro-benzaldehyde imine. U(eq) is defined as one third of
the trace of the orthogonalized Uij tensor.
Chapter 6. Experimental 208
Table 6.6: Bond lengths [A] and angles [°] for N-Adamantyl-p-chloro-benzaldehyde
imine.
Cl(1)-C(15) 1.7422(12)
N(1)-C(11) 1.2709(16)
N(1)-C(1) 1.4754(14)
C(1)-C(7) 1.5357(16)
C(1)-C(2) 1.5416(16)
C(1)-C(6) 1.5428(16)
C(2)-C(3) 1.5387(16)
C(2)-H(2A) 0.994(18)
C(2)-H(2B) 0.977(18)
C(3)-C(10) 1.5370(17)
C(3)-C(4) 1.5385(17)
C(3)-H(3) 0.978(18)
C(4)-C(5) 1.5357(17)
C(4)-H(4A) 0.981(17)
C(4)-H(4B) 1.007(18)
C(5)-C(9) 1.5360(17)
C(5)-C(6) 1.5391(16)
C(5)-H(5) 0.993(18)
C(6)-H(6A) 0.992(18)
C(6)-H(6B) 0.983(18)
C(7)-C(8) 1.5391(16)
C(7)-H(7A) 0.991(18)
C(7)-H(7B) 1.004(17)
C(8)-C(10) 1.5335(17)
C(8)-C(9) 1.5368(17)
C(8)-H(8) 0.999(18)
C(9)-H(9A) 0.964(17)
C(9)-H(9B) 0.999(18)
C(10)-H(10A) 0.987(18)
C(10)-H(10B) 0.969(18)
C(11)-C(12) 1.4811(16)
C(11)-H(11) 0.983(18)
C(12)-C(17) 1.3957(17)
C(12)-C(13) 1.3995(17)
C(13)-C(14) 1.3888(16)
C(13)-H(13) 0.974(18)
C(14)-C(15) 1.3931(17)
C(14)-H(14) 0.952(18)
C(15)-C(16) 1.3870(18)
C(16)-C(17) 1.3946(17)
C(16)-H(16) 0.975(18)
C(17)-H(17) 0.953(18)
C(11)-N(1)-C(1) 119.87(10)
N(1)-C(1)-C(7) 116.02(9)
N(1)-C(1)-C(2) 106.59(9)
C(7)-C(1)-C(2) 108.94(10)
N(1)-C(1)-C(6) 107.58(9)
C(7)-C(1)-C(6) 108.73(9)
Chapter 6. Experimental 209
C(2)-C(1)-C(6) 108.79(9)
C(3)-C(2)-C(1) 110.38(9)
C(3)-C(2)-H(2A) 111.2(10)
C(1)-C(2)-H(2A) 108.3(10)
C(3)-C(2)-H(2B) 110.5(10)
C(1)-C(2)-H(2B) 108.5(10)
H(2A)-C(2)-H(2B) 107.7(14)
C(10)-C(3)-C(4) 109.49(10)
C(10)-C(3)-C(2) 109.41(10)
C(4)-C(3)-C(2) 109.07(10)
C(10)-C(3)-H(3) 108.2(10)
C(4)-C(3)-H(3) 110.8(10)
C(2)-C(3)-H(3) 109.8(10)
C(5)-C(4)-C(3) 109.52(10)
C(5)-C(4)-H(4A) 109.9(10)
C(3)-C(4)-H(4A) 110.0(10)
C(5)-C(4)-H(4B) 110.5(10)
C(3)-C(4)-H(4B) 109.5(10)
H(4A)-C(4)-H(4B) 07.4(14)
C(4)-C(5)-C(9) 109.52(10)
C(4)-C(5)-C(6) 109.41(10)
C(9)-C(5)-C(6) 109.50(10)
C(4)-C(5)-H(5) 108.1(10)
C(9)-C(5)-H(5) 111.2(10)
C(6)-C(5)-H(5) 109.1(10)
C(5)-C(6)-C(1) 110.10(9)
C(5)-C(6)-H(6A) 110.5(10)
C(1)-C(6)-H(6A) 110.9(10)
C(5)-C(6)-H(6B) 110.0(10)
C(1)-C(6)-H(6B) 109.3(10)
H(6A)-C(6)-H(6B) 106.0(14)
C(1)-C(7)-C(8) 110.13(9)
C(1)-C(7)-H(7A) 109.2(10)
C(8)-C(7)-H(7A) 109.7(10)
C(1)-C(7)-H(7B) 109.9(10)
C(8)-C(7)-H(7B) 109.4(10)
H(7A)-C(7)-H(7B) 108.5(14)
C(10)-C(8)-C(9) 109.22(10)
C(10)-C(8)-C(7) 109.82(10)
C(9)-C(8)-C(7) 109.57(10)
C(10)-C(8)-H(8) 109.3(10)
C(9)-C(8)-H(8) 109.0(10)
C(7)-C(8)-H(8) 110.0(10)
C(5)-C(9)-C(8) 109.37(10)
C(5)-C(9)-H(9A) 109.2(11)
C(8)-C(9)-H(9A) 109.1(10)
C(5)-C(9)-H(9B) 110.5(10)
C(8)-C(9)-H(9B) 110.2(10)
H(9A)-C(9)-H(9B) 108.4(14)
C(8)-C(10)-C(3) 109.50(10)
C(8)-C(10)-H(10A) 110.8(10)
C(3)-C(10)-H(10A) 110.3(10)
C(8)-C(10)-H(10B) 109.2(10)
C(3)-C(10)-H(10B) 111.1(11)
Chapter 6. Experimental 210
H(10A)-C(10)-H(10B) 105.9(14)
N(1)-C(11)-C(12) 121.77(11)
N(1)-C(11)-H(11) 122.4(10)
C(12)-C(11)-H(11) 115.8(10)
C(17)-C(12)-C(13) 119.21(11)
C(17)-C(12)-C(11) 119.50(11)
C(13)-C(12)-C(11) 121.28(11)
C(14)-C(13)-C(12) 120.89(11)
C(14)-C(13)-H(13) 120.4(10)
C(12)-C(13)-H(13) 118.7(10)
C(13)-C(14)-C(15) 118.58(11)
C(13)-C(14)-H(14) 121.5(11)
C(15)-C(14)-H(14) 119.8(11)
C(16)-C(15)-C(14) 121.89(11)
C(16)-C(15)-Cl(1) 119.01(9)
C(14)-C(15)-Cl(1) 119.09(9)
C(15)-C(16)-C(17) 118.74(11)
C(15)-C(16)-H(16) 119.8(10)
C(17)-C(16)-H(16) 121.4(10)
C(16)-C(17)-C(12) 120.69(11)
C(16)-C(17)-H(17) 119.5(11)
C(12)-C(17)-H(17) 119.7(11)
Chapter 6. Experimental 211
Table 6.7: Torsion angles [°] for N-Adamantyl-p-chloro-benzaldehyde imine.
C(11)-N(1)-C(1)-C(7) 3.15(15)
C(11)-N(1)-C(1)-C(2) 124.63(11)
C(11)-N(1)-C(1)-C(6) -118.82(12)
N(1)-C(1)-C(2)-C(3) 175.00(9)
C(7)-C(1)-C(2)-C(3) -59.12(12)
C(6)-C(1)-C(2)-C(3) 59.26(12)
C(1)-C(2)-C(3)-C(10) 59.66(13)
C(1)-C(2)-C(3)-C(4) -60.09(13)
C(10)-C(3)-C(4)-C(5) -59.50(12)
C(2)-C(3)-C(4)-C(5) 60.20(12)
C(3)-C(4)-C(5)-C(9) 59.69(12)
C(3)-C(4)-C(5)-C(6) -60.34(12)
C(4)-C(5)-C(6)-C(1) 60.02(12)
C(9)-C(5)-C(6)-C(1) -60.01(13)
N(1)-C(1)-C(6)-C(5) -174.12(9)
C(7)-C(1)-C(6)-C(5) 59.49(12)
C(2)-C(1)-C(6)-C(5) -59.02(12)
N(1)-C(1)-C(7)-C(8) 179.14(9)
C(2)-C(1)-C(7)-C(8) 58.92(12)
C(6)-C(1)-C(7)-C(8) -59.50(12)
C(1)-C(7)-C(8)-C(10) -59.81(12)
C(1)-C(7)-C(8)-C(9) 60.15(12)
C(4)-C(5)-C(9)-C(8) -60.26(12)
C(6)-C(5)-C(9)-C(8) 59.71(13)
C(10)-C(8)-C(9)-C(5) 60.58(12)
C(7)-C(8)-C(9)-C(5) -59.75(13)
C(9)-C(8)-C(10)-C(3) -60.49(12)
C(7)-C(8)-C(10)-C(3) 59.69(12)
C(4)-C(3)-C(10)-C(8) 60.00(12)
C(2)-C(3)-C(10)-C(8) -59.49(13)
C(1)-N(1)-C(11)-C(12) 179.41(10)
N(1)-C(11)-C(12)-C(17) -168.44(11)
N(1)-C(11)-C(12)-C(13) 9.78(17)
C(17)-C(12)-C(13)-C(14) 1.00(17)
C(11)-C(12)-C(13)-C(14) -177.22(10)
C(12)-C(13)-C(14)-C(15) -1.16(17)
C(13)-C(14)-C(15)-C(16) 0.75(17)
C(13)-C(14)-C(15)-Cl(1) -178.44(9)
C(14)-C(15)-C(16)-C(17) -0.19(18)
Cl(1)-C(15)-C(16)-C(17) 179.00(9)
C(15)-C(16)-C(17)-C(12) 0.03(18)
C(13)-C(12)-C(17)-C(16) -0.43(18)
C(11)-C(12)-C(17)-C(16) 177.83(10)
Chapter 6. Experimental 212
6.6.4. Crystal data and structure refinement for N-Adamantyl-p-bromo-
benzaldehyde imine
Empirical formula C17H20BrN
Formula weight 318.25
Temperature 100(2) K
Wavelength 0.71073 A°
Crystal system, space group Monoclinic, C2/c
Unit cell dimensions a = 27.680(3) A° alpha = 90 °
b = 6.5071(3) A° beta = 108.150(8) °
c = 16.548(2) A° gamma = 90 °
Volume 2832.3(5) A°3
Z, Calculated density 8, 1.493 Mg/m3
Absorption coefficient 2.889 mm-1
F(000) 1312
Crystal size 0.26 x 0.21 x 0.13 mm
Theta range for data collection 3.87 to 28.69 deg.
Limiting indices -37 ≤ h ≤ 36, -8 ≤ k ≤ 8, -22 ≤ l ≤ 22
Reflections collected / unique 25383 / 3650 [R(int) = 0.0396]
Completeness to theta = 28.69 99.7 %
Absorption correction Semi-empirical from equivalents
Max. and min. transmission 1.000 and 0.771
Refinement method Full-matrix least-squares on F2
Data / restraints / parameters 3650 / 0 / 232
Goodness-of-fit on F2 1.072
Final R indices [I>2sigma(I)] R1 = 0.0268, wR2 = 0.0530
R indices (all data) R1 = 0.0431, wR2 = 0.0570
Largest diff. peak and hole 0.377 and -0.357 e.A°-3
Chapter 6. Experimental 213
________________________________________________________________ x y z U(eq) ________________________________________________________________ Br(1) 6361(1) 5383(1) 5419(1) 19(1) N(1) 4212(1) 8943(2) 6254(1) 14(1) C(1) 3746(1) 9260(3) 6496(1) 12(1) C(2) 3826(1) 11259(3) 7018(1) 15(1) C(3) 3342(1) 11815(3) 7234(1) 15(1) C(4) 2905(1) 12122(3) 6407(1) 17(1) C(5) 2816(1) 10126(3) 5889(1) 15(1) C(6) 3300(1) 9561(3) 5673(1) 14(1) C(7) 3610(1) 7524(3) 7016(1) 13(1) C(8) 3125(1) 8082(3) 7231(1) 15(1) C(9) 2684(1) 8388(3) 6408(1) 17(1) C(10) 3210(1) 10070(3) 7755(1) 17(1) C(11) 4457(1) 7269(3) 6443(1) 13(1) C(12) 4921(1) 6860(3) 6207(1) 13(1) C(13) 5158(1) 8407(3) 5883(1) 14(1) C(14) 5582(1) 7982(3) 5634(1) 14(1) C(15) 5770(1) 5985(3) 5724(1) 14(1) C(16) 5544(1) 4423(3) 6046(1) 15(1) C(17) 5118(1) 4874(3) 6287(1) 15(1) ________________________________________________________________ Table 6.11: Atomic coordinates ( x 104) and equivalent isotropic displacement parameters
(A2 x 103) for N-Adamantyl-p-bromo-benzaldehyde imine. U(eq) is defined as one third of
the trace of the orthogonalized Uij tensor.
Chapter 6. Experimental 214
Table 6.12: Bond lengths [A] and angles [°] for N-Adamantyl-p-bromo-benzaldehyde
imine.
Br(1)-C(15) 1.8964(17)
N(1)-C(11) 1.270(2)
N(1)-C(1) 1.479(2)
C(1)-C(7) 1.536(2)
C(1)-C(2) 1.539(3)
C(1)-C(6) 1.540(2)
C(2)-C(3) 1.534(3)
C(2)-H(2A) 0.97(2)
C(2)-H(2B) 1.01(2)
C(3)-C(4) 1.531(3)
C(3)-C(10) 1.537(3)
C(3)-H(3) 0.96(2)
C(4)-C(5) 1.534(3)
C(4)-H(4A) 0.99(2)
C(4)-H(4B) 1.00(2)
C(5)-C(9) 1.532(3)
C(5)-C(6) 1.534(2)
C(5)-H(5) 0.95(2)
C(6)-H(6A) 0.99(2)
C(6)-H(6B) 0.93(2)
C(7)-C(8) 1.538(2)
C(7)-H(7A) 0.96(3)
C(7)-H(7B) 1.05(2)
C(8)-C(9) 1.533(3)
C(8)-C(10) 1.534(3)
C(8)-H(8) 1.01(2)
C(9)-H(9A) 0.97(2)
C(9)-H(9B) 1.00(2)
C(10)-H(10A) 0.99(2)
C(10)-H(10B) 1.04(2)
C(11)-C(12) 1.476(2)
C(11)-H(11) 0.95(2)
C(12)-C(17) 1.393(3)
C(12)-C(13) 1.397(3)
C(13)-C(14) 1.389(3)
C(13)-H(13) 0.95(2)
C(14)-C(15) 1.391(3)
C(14)-H(14) 0.95(2)
C(15)-C(16) 1.385(3)
C(16)-C(17) 1.389(3)
C(16)-H(16) 0.93(3)
C(17)-H(17) 0.96(2)
C(11)-N(1)-C(1) 119.84(16)
N(1)-C(1)-C(7) 115.80(14)
N(1)-C(1)-C(2) 106.54(14)
C(7)-C(1)-C(2) 108.94(15)
N(1)-C(1)-C(6) 107.81(14)
C(7)-C(1)-C(6) 108.62(15)
C(2)-C(1)-C(6) 108.96(15)
C(3)-C(2)-C(1) 110.26(15)
C(3)-C(2)-H(2A) 110.8(14)
C(1)-C(2)-H(2A) 107.2(14)
Chapter 6. Experimental 215
C(3)-C(2)-H(2B) 108.6(13)
C(1)-C(2)-H(2B) 110.0(13)
H(2A)-C(2)-H(2B) 110.0(19)
C(4)-C(3)-C(2) 109.12(16)
C(4)-C(3)-C(10) 109.78(16)
C(2)-C(3)-C(10) 109.53(15)
C(4)-C(3)-H(3) 109.8(14)
C(2)-C(3)-H(3) 108.6(14)
C(10)-C(3)-H(3) 110.0(14)
C(3)-C(4)-C(5) 109.49(15)
C(3)-C(4)-H(4A) 110.4(13)
C(5)-C(4)-H(4A) 108.8(14)
C(3)-C(4)-H(4B) 112.8(13)
C(5)-C(4)-H(4B) 108.2(13)
H(4A)-C(4)-H(4B) 107.0(19)
C(9)-C(5)-C(6) 109.33(15)
C(9)-C(5)-C(4) 109.66(15)
C(6)-C(5)-C(4) 109.49(16)
C(9)-C(5)-H(5) 109.9(14)
C(6)-C(5)-H(5) 109.8(14)
C(4)-C(5)-H(5) 108.7(14)
C(5)-C(6)-C(1) 110.07(14)
C(5)-C(6)-H(6A) 107.2(13)
C(1)-C(6)-H(6A) 110.5(13)
C(5)-C(6)-H(6B) 108.9(14)
C(1)-C(6)-H(6B) 110.4(15)
H(6A)-C(6)-H(6B) 109.6(19)
C(1)-C(7)-C(8) 109.92(15)
C(1)-C(7)-H(7A) 109.3(14)
C(8)-C(7)-H(7A) 109.1(14)
C(1)-C(7)-H(7B) 108.9(13)
C(8)-C(7)-H(7B) 111.0(13)
H(7A)-C(7)-H(7B) 108.5(19)
C(9)-C(8)-C(10) 109.44(15)
C(9)-C(8)-C(7) 109.60(15)
C(10)-C(8)-C(7) 109.77(15)
C(9)-C(8)-H(8) 109.3(13)
C(10)-C(8)-H(8) 107.5(13)
C(7)-C(8)-H(8) 111.1(13)
C(5)-C(9)-C(8) 109.39(15)
C(5)-C(9)-H(9A) 109.8(14)
C(8)-C(9)-H(9A) 108.9(14)
C(5)-C(9)-H(9B) 107.8(13)
C(8)-C(9)-H(9B) 110.5(13)
H(9A)-C(9)-H(9B) 110.3(19)
C(8)-C(10)-C(3) 109.09(15)
C(8)-C(10)-H(10A) 109.3(14)
C(3)-C(10)-H(10A) 108.6(14)
C(8)-C(10)-H(10B) 111.5(13)
C(3)-C(10)-H(10B) 109.2(13)
H(10A)-C(10)-H(10B) 109.1(18)
N(1)-C(11)-C(12) 122.12(17)
N(1)-C(11)-H(11) 122.7(14)
C(12)-C(11)-H(11) 115.2(14)
C(17)-C(12)-C(13) 119.23(17)
C(17)-C(12)-C(11) 119.27(17)
Chapter 6. Experimental 216
C(13)-C(12)-C(11) 121.48(17)
C(14)-C(13)-C(12) 120.83(17)
C(14)-C(13)-H(13) 119.9(14)
C(12)-C(13)-H(13) 119.2(14)
C(13)-C(14)-C(15) 118.50(17)
C(13)-C(14)-H(14) 122.0(14)
C(15)-C(14)-H(14) 119.4(14)
C(16)-C(15)-C(14) 121.87(17)
C(16)-C(15)-Br(1) 118.82(14)
C(14)-C(15)-Br(1) 119.30(14)
C(15)-C(16)-C(17) 118.84(18)
C(15)-C(16)-H(16) 118.7(14)
C(17)-C(16)-H(16) 122.5(14)
C(16)-C(17)-C(12) 120.73(18)
C(16)-C(17)-H(17) 119.4(14)
C(12)-C(17)-H(17) 119.8(14)
Chapter 6. Experimental 217
Table 6.13: Torsion angles [°] for N-Adamantyl-p-bromo-benzaldehyde imine.
C(11)-N(1)-C(1)-C(7) 3.3(2)
C(11)-N(1)-C(1)-C(2) 124.63(18)
C(11)-N(1)-C(1)-C(6) -118.54(18)
N(1)-C(1)-C(2)-C(3) 175.15(15)
C(7)-C(1)-C(2)-C(3) -59.3(2)
C(6)-C(1)-C(2)-C(3) 59.08(19)
C(1)-C(2)-C(3)-C(4) -60.2(2)
C(1)-C(2)-C(3)-C(10) 60.0(2)
C(2)-C(3)-C(4)-C(5) 60.5(2)
C(10)-C(3)-C(4)-C(5) -59.57(19)
C(3)-C(4)-C(5)-C(9) 59.53(19)
C(3)-C(4)-C(5)-C(6) -60.42(19)
C(9)-C(5)-C(6)-C(1) -60.4(2)
C(4)-C(5)-C(6)-C(1) 59.7(2)
N(1)-C(1)-C(6)-C(5) -173.95(15)
C(7)-C(1)-C(6)-C(5) 59.9(2)
C(2)-C(1)-C(6)-C(5) -58.7(2)
N(1)-C(1)-C(7)-C(8) 179.11(15)
C(2)-C(1)-C(7)-C(8) 59.09(19)
C(6)-C(1)-C(7)-C(8) -59.47(19)
C(1)-C(7)-C(8)-C(9) 60.1(2)
C(1)-C(7)-C(8)-C(10) -60.2(2)
C(6)-C(5)-C(9)-C(8) 60.0(2)
C(4)-C(5)-C(9)-C(8) -60.02(19)
C(10)-C(8)-C(9)-C(5) 60.52(19)
C(7)-C(8)-C(9)-C(5) -59.9(2)
C(9)-C(8)-C(10)-C(3) -60.31(19)
C(7)-C(8)-C(10)-C(3) 60.02(19)
C(4)-C(3)-C(10)-C(8) 59.96(19)
C(2)-C(3)-C(10)-C(8) -59.8(2)
C(1)-N(1)-C(11)-C(12) 179.16(16)
N(1)-C(11)-C(12)-C(17) -168.05(18)
N(1)-C(11)-C(12)-C(13) 10.2(3)
C(17)-C(12)-C(13)-C(14) 0.7(3)
C(11)-C(12)-C(13)-C(14) -177.54(17)
C(12)-C(13)-C(14)-C(15) -0.8(3)
C(13)-C(14)-C(15)-C(16) 0.6(3)
C(13)-C(14)-C(15)-Br(1) -178.17(13)
C(14)-C(15)-C(16)-C(17) -0.3(3)
Br(1)-C(15)-C(16)-C(17) 178.54(13)
C(15)-C(16)-C(17)-C(12) 0.1(3)
C(13)-C(12)-C(17)-C(16) -0.3(3)
C(11)-C(12)-C(17)-C(16) 177.96(17)
Chapter 6. Experimental 218
6.6.5. Crystal data and structure refinement for N-Adamantyl-p-methoxy-
benzaldehyde imine
Empirical formula C18H23NO
Formula weight 269.37
Temperature 100(2) K
Wavelength 0.71073 A°
Crystal system, space group Monoclinic, P2 1
Unit cell dimensions a = 6.7598(4) A° alpha = 90°
b = 6.7421(2) A° beta = 93.646(4) °
c = 15.7289(5) A° gamma = 90°
Volume 715.40(5) A3
Z, Calculated density 2, 1.251 Mg/m3
Absorption coefficient 0.076 mm-1
F(000) 292
Crystal size 0.33 x 0.24 x 0.18 mm
Theta range for data collection 3.36 to 27.87°
Limiting indices -8 ≤ h≤ 8, -8 ≤ k ≤ 8, -20 ≤ l ≤ 20
Reflections collected / unique 18633 / 3395 [R(int) = 0.0282]
Completeness to theta = 27.87 99.7 %
Absorption correction Semi-empirical from equivalents
Max. and min. transmission 1.000 and 0.944
Refinement method Full-matrix least-squares on F2
Data / restraints / parameters 3395 / 1 / 251
Goodness-of-fit on F2 1.049
Final R indices [I>2sigma(I)] R1 = 0.0375, wR2 = 0.0963
R indices (all data) R1 = 0.0434, wR2 = 0.0991
Absolute structure parameter 0.0(15)
Largest diff. peak and hole 0.270 and -0.215 e.A°-3
Chapter 6. Experimental 219
________________________________________________________________
x y z U(eq)
________________________________________________________________
O(1) 5254(1) 318(2) 8216(1) 18(1)
N(1) 9507(2) 242(2) 12043(1) 16(1)
C(1) 11067(2) 342(2) 12747(1) 14(1)
C(2) 10711(3) 2225(2) 13272(1) 18(1)
C(3) 12190(3) 2299(2) 14056(1) 19(1)
C(4) 11900(2) 469(3) 14615(1) 20(1)
C(5) 12276(3) -1413(2) 14101(1) 18(1)
C(6) 10811(3) -1484(2) 13315(1) 17(1)
C(7) 13214(2) 383(3) 12472(1) 15(1)
C(8) 14682(2) 451(3) 13257(1) 17(1)
C(9) 14403(3) -1380(2) 13811(1) 20(1)
C(10) 14316(3) 2330(2) 13770(1) 19(1)
C(11) 9990(2) 551(2) 11292(1) 14(1)
C(12) 8608(2) 478(2) 10527(1) 14(1)
C(13) 6618(2) -55(2) 10522(1) 16(1)
C(14) 5429(2) -145(2) 9768(1) 16(1)
C(15) 6245(2) 318(2) 9000(1) 14(1)
C(16) 8239(2) 834(2) 8995(1) 16(1)
C(17) 9393(2) 912(2) 9747(1) 16(1)
C(18) 3168(2) -9(3) 8169(1) 23(1)
________________________________________________________________
Table 6.14: Atomic coordinates ( x 104) and equivalent isotropic displacement parameters
(A2 x 103) for N-Adamantyl-p-methoxy-benzaldehyde imine. U(eq) is defined as one third
of the trace of the orthogonalized Uij tensor.
Chapter 6. Experimental 220
Table 6.15: Bond lengths [A] and angles [°] for N-Adamantyl-p-methoxy-benzaldehyde
imine.
O(1)-C(15) 1.3642(13)
O(1)-C(18) 1.4246(17)
N(1)-C(11) 1.2637(17)
N(1)-C(1) 1.4817(15)
C(1)-C(6) 1.537(2)
C(1)-C(7) 1.5406(16)
C(1)-C(2) 1.542(2)
C(2)-C(3) 1.539(2)
C(2)-H(2A) 0.98(3)
C(2)-H(2B) 1.02(3)
C(3)-C(10) 1.533(2)
C(3)-C(4) 1.534(2)
C(3)-H(3) 1.01(3)
C(4)-C(5) 1.534(2)
C(4)-H(4A) 0.98(2)
C(4)-H(4B) 1.02(2)
C(5)-C(6) 1.534(2)
C(5)-C(9) 1.536(2)
C(5)-H(5) 0.99(3)
C(6)-H(6A) 0.98(3)
C(6)-H(6B) 1.00(2)
C(7)-C(8) 1.5345(16)
C(7)-H(7A) 0.99(3)
C(7)-H(7B) 1.01(3)
C(8)-C(9) 1.530(2)
C(8)-C(10) 1.531(2)
C(8)-H(8) 0.99(2)
C(9)-H(9A) 1.02(2)
C(9)-H(9B) 0.98(3)
C(10)-H(10A) 0.98(3)
C(10)-H(10B) 0.99(3)
C(11)-C(12) 1.4761(16)
C(11)-H(11) 0.98(2)
C(12)-C(13) 1.3920(18)
C(12)-C(17) 1.3984(18)
C(13)-C(14) 1.3908(19)
C(13)-H(13) 0.96(2)
C(14)-C(15) 1.3960(17)
C(14)-H(14) 0.95(2)
C(15)-C(16) 1.3929(18)
C(16)-C(17) 1.3755(19)
C(16)-H(16) 0.95(2)
C(17)-H(17) 0.98(2)
C(18)-H(18A) 0.99(2)
C(18)-H(18B) 0.96(2)
C(18)-H(18C) 1.01(2)
C(15)-O(1)-C(18) 118.36(10)
C(11)-N(1)-C(1) 118.53(10)
N(1)-C(1)-C(6) 107.29(12)
N(1)-C(1)-C(7) 115.43(9)
C(6)-C(1)-C(7) 108.72(12)
N(1)-C(1)-C(2) 108.01(12)
C(6)-C(1)-C(2) 108.74(10)
C(7)-C(1)-C(2) 108.50(12)
Chapter 6. Experimental 221
C(3)-C(2)-C(1) 109.89(12)
C(3)-C(2)-H(2A) 111.1(15)
C(1)-C(2)-H(2A) 108.0(15)
C(3)-C(2)-H(2B) 110.0(14)
C(1)-C(2)-H(2B) 108.4(15)
H(2A)-C(2)-H(2B) 109(2)
C(10)-C(3)-C(4) 109.57(13)
C(10)-C(3)-C(2) 109.77(15)
C(4)-C(3)-C(2) 109.50(13)
C(10)-C(3)-H(3) 108.8(15)
C(4)-C(3)-H(3) 109.7(15)
C(2)-C(3)-H(3) 109.5(14)
C(5)-C(4)-C(3) 109.35(10)
C(5)-C(4)-H(4A) 110.7(15)
C(3)-C(4)-H(4A) 110.0(15)
C(5)-C(4)-H(4B) 108.8(14)
C(3)-C(4)-H(4B) 109.9(14)
H(4A)-C(4)-H(4B) 108.1(15)
C(4)-C(5)-C(6) 109.30(13)
C(4)-C(5)-C(9) 109.50(13)
C(6)-C(5)-C(9) 109.26(14)
C(4)-C(5)-H(5) 111.3(15)
C(6)-C(5)-H(5) 110.9(15)
C(9)-C(5)-H(5) 106.5(15)
C(5)-C(6)-C(1) 110.64(12)
C(5)-C(6)-H(6A) 110.2(16)
C(1)-C(6)-H(6A) 110.5(14)
C(5)-C(6)-H(6B) 111.5(14)
C(1)-C(6)-H(6B) 109.5(15)
H(6A)-C(6)-H(6B) 104(2)
C(8)-C(7)-C(1) 110.32(9)
C(8)-C(7)-H(7A) 111.1(14)
C(1)-C(7)-H(7A) 107.7(15)
C(8)-C(7)-H(7B) 106.6(14)
C(1)-C(7)-H(7B) 112.6(15)
H(7A)-C(7)-H(7B) 108.6(15)
C(9)-C(8)-C(10) 109.65(10)
C(9)-C(8)-C(7) 109.74(13)
C(10)-C(8)-C(7) 109.33(13)
C(9)-C(8)-H(8) 111.8(14)
C(10)-C(8)-H(8) 108.8(15)
C(7)-C(8)-H(8) 107.5(11)
C(8)-C(9)-C(5) 109.44(13)
C(8)-C(9)-H(9A) 108.6(15)
C(5)-C(9)-H(9A) 109.1(15)
C(8)-C(9)-H(9B) 110.2(15)
C(5)-C(9)-H(9B) 111.1(15)
H(9A)-C(9)-H(9B) 108(2)
C(8)-C(10)-C(3) 109.24(12)
C(8)-C(10)-H(10A) 109.5(15)
C(3)-C(10)-H(10A) 109.6(16)
C(8)-C(10)-H(10B) 109.8(15)
C(3)-C(10)-H(10B) 110.3(15)
H(10A)-C(10)-H(10B) 108(2)
N(1)-C(11)-C(12) 124.66(11)
N(1)-C(11)-H(11) 124.2(12)
Chapter 6. Experimental 222
C(12)-C(11)-H(11) 111.1(11)
C(13)-C(12)-C(17) 118.05(11)
C(13)-C(12)-C(11) 125.05(11)
C(17)-C(12)-C(11) 116.86(11)
C(14)-C(13)-C(12) 121.42(12)
C(14)-C(13)-H(13) 118.3(13)
C(12)-C(13)-H(13) 120.3(13)
C(13)-C(14)-C(15) 119.36(12)
C(13)-C(14)-H(14) 120.3(13)
C(15)-C(14)-H(14) 120.4(13)
O(1)-C(15)-C(16) 114.53(10)
O(1)-C(15)-C(14) 125.74(11)
C(16)-C(15)-C(14) 119.73(11)
C(17)-C(16)-C(15) 120.09(12)
C(17)-C(16)-H(16) 121.4(14)
C(15)-C(16)-H(16) 118.5(13)
C(16)-C(17)-C(12) 121.34(12)
C(16)-C(17)-H(17) 120.2(12)
C(12)-C(17)-H(17) 118.4(12)
O(1)-C(18)-H(18A) 112.0(13)
O(1)-C(18)-H(18B) 104.2(12)
H(18A)-C(18)-H(18B) 109(2)
O(1)-C(18)-H(18C) 109.2(12)
H(18A)-C(18)-H(18C) 108.0(18)
H(18B)-C(18)-H(18C) 114.7(18)
Chapter 6. Experimental 223
Table 6.16: Torsion angles [°] for N-Adamantyl-p-methoxy-benzaldehyde imine.
C(11)-N(1)-C(1)-C(6) -133.68(15)
C(11)-N(1)-C(1)-C(7) -12.3(2)
C(11)-N(1)-C(1)-C(2) 109.26(15)
N(1)-C(1)-C(2)-C(3) 175.13(12)
C(6)-C(1)-C(2)-C(3) 59.01(15)
C(7)-C(1)-C(2)-C(3) -59.08(17)
C(1)-C(2)-C(3)-C(10) 60.04(17)
C(1)-C(2)-C(3)-C(4) -60.28(18)
C(10)-C(3)-C(4)-C(5) -60.05(15)
C(2)-C(3)-C(4)-C(5) 60.40(15)
C(3)-C(4)-C(5)-C(6) -59.90(15)
C(3)-C(4)-C(5)-C(9) 59.75(15)
C(4)-C(5)-C(6)-C(1) 59.87(17)
C(9)-C(5)-C(6)-C(1) -59.94(17)
N(1)-C(1)-C(6)-C(5) -175.67(12)
C(7)-C(1)-C(6)-C(5) 58.85(16)
C(2)-C(1)-C(6)-C(5) -59.09(15)
N(1)-C(1)-C(7)-C(8) -179.06(14)
C(6)-C(1)-C(7)-C(8) -58.49(17)
C(2)-C(1)-C(7)-C(8) 59.61(16)
C(1)-C(7)-C(8)-C(9) 59.74(17)
C(1)-C(7)-C(8)-C(10) -60.56(17)
C(10)-C(8)-C(9)-C(5) 60.12(15)
C(7)-C(8)-C(9)-C(5) -59.98(16)
C(4)-C(5)-C(9)-C(8) -59.82(17)
C(6)-C(5)-C(9)-C(8) 59.86(17)
C(9)-C(8)-C(10)-C(3) -60.26(15)
C(7)-C(8)-C(10)-C(3) 60.09(16)
C(4)-C(3)-C(10)-C(8) 60.19(17)
C(2)-C(3)-C(10)-C(8) -60.09(16)
C(1)-N(1)-C(11)-C(12) 179.19(14)
N(1)-C(11)-C(12)-C(13) -4.0(2)
N(1)-C(11)-C(12)-C(17) 178.34(15)
C(17)-C(12)-C(13)-C(14) -0.4(2)
C(11)-C(12)-C(13)-C(14) -178.00(14)
C(12)-C(13)-C(14)-C(15) -0.3(2)
C(18)-O(1)-C(15)-C(16) -174.19(14)
C(18)-O(1)-C(15)-C(14) 5.9(2)
C(13)-C(14)-C(15)-O(1) -179.11(14)
C(13)-C(14)-C(15)-C(16) 1.0(2)
O(1)-C(15)-C(16)-C(17) 179.18(13)
C(14)-C(15)-C(16)-C(17) -0.9(2)
C(15)-C(16)-C(17)-C(12) 0.1(2)
C(13)-C(12)-C(17)-C(16) 0.5(2)
C(11)-C(12)-C(17)-C(16) 178.29(13)
Chapter 6. Experimental 224
6.6.6. Crystal data and structure refinement for 16a
Empirical formula C22H28ClN
Formula weight 341.90
Temperature 100(2) K
Wavelength 0.71073 A°
Crystal system, space group Monoclinic, P21/c
Unit cell dimensions a = 9.253(1) A° alpha = 90°
b = 15.603(1) A° beta = 91.06(1)°
c = 12.500(1) A° gamma = 90°
Volume 1804.4(3) A3
Z, Calculated density 4, 1.259 Mg/m3
Absorption coefficient 0.215 mm-1
F(000) 736
Crystal size 0.25 x 0.23 x 0.20 mm
Theta range for data collection 3.06 to 26.37 °
Limiting indices -11 ≤ h ≤ 11, -19 ≤ k ≤ 19, -15 ≤ l ≤ 15
Reflections collected / unique 34333 / 3687 [R(int) = 0.0456]
Completeness to theta = 26.37 99.8 %
Absorption correction Semi-empirical from equivalents
Max. and min. transmission 1.000 and 0.948
Refinement method Full-matrix least-squares on F2
Data / restraints / parameters 3687 / 13 / 254
Goodness-of-fit on F2 1.136
Final R indices [I>2sigma(I)] R1 = 0.0417, wR2 = 0.0910
R indices (all data) R1 = 0.0555, wR2 = 0.0968
Largest diff. peak and hole 0.246 and -0.250 e.A°-3
Chapter 6. Experimental 225
_______________________ _______________________________________ x y z U(eq) _ _______________________________________________________________ Cl(1) 8670(1) 794(1) 4134(1) 34(1) N(1) 5350(2) 1335(1) -627(1) 20(1) C(1) 4537(2) 2137(1) -454(1) 18(1) C(2) 5025(2) 2880(1) -1172(1) 25(1) C(3) 4066(2) 3670(1) -1003(2) 29(1) C(4) 2496(2) 3446(1) -1290(2) 29(1) C(5) 1988(2) 2716(1) -564(2) 26(1) C(6) 2947(2) 1929(1) -722(2) 24(1) C(7) 4637(2) 2425(1) 717(1) 23(1) C(8) 3680(2) 3217(1) 883(1) 28(1) C(9) 2105(2) 3004(1) 607(2) 29(1) C(10) 4191(2) 3947(1) 166(2) 32(1) C(11) 6931(2) 1356(1) -495(1) 22(1) C(12) 7374(2) 1216(1) 669(1) 20(1) C(13) 8441(2) 1719(1) 1156(1) 23(1) C(14) 8849(2) 1592(1) 2219(1) 25(1) C(15) 8182(2) 954(1) 2792(1) 23(1) C(16) 7125(2) 440(1) 2326(1) 24(1) C(17) 6731(2) 573(1) 1267(1) 22(1) C(18) 7583(2) 658(2) -1216(2) 34(1) C(19) 7154(10) 681(6) -2408(4) 29(2) C(20) 8266(9) 957(6) -2930(7) 27(2) C(21) 9656(13) 1015(10) -2277(9) 31(3) C(22) 9229(5) 538(5) -1254(9) 28(2) C(19') 7296(10) 968(6) -2396(5) 24(2) C(20') 8715(9) 859(6) -3014(9) 23(2) C(21') 9784(14) 867(10) -2112(10) 28(2) C(22') 9243(7) 805(7) -1159(9) 25(2) _______________________________________________________________ Table 6.20: Atomic coordinates ( x 104) and equivalent isotropic displacement parameters
(A2 x 103) for 16a. U(eq) is defined as one third of the trace of the orthogonalized Uij
tensor.
Chapter 6. Experimental 226
Table 6.21: Bond lengths [A] and angles [°] for 16a.
Cl(1)-C(15) 1.7463(17)
N(1)-C(11) 1.469(2)
N(1)-C(1) 1.478(2)
N(1)-H(1) 0.9398
C(1)-C(7) 1.532(2)
C(1)-C(6) 1.537(2)
C(1)-C(2) 1.539(2)
C(2)-C(3) 1.537(3)
C(2)-H(2A) 0.9900
C(2)-H(2B) 0.9900
C(3)-C(10) 1.526(3)
C(3)-C(4) 1.530(3)
C(3)-H(3A) 1.0000
C(4)-C(5) 1.536(3)
C(4)-H(4A) 0.9900
C(4)-H(4B) 0.9900
C(5)-C(6) 1.530(3)
C(5)-C(9) 1.533(3)
C(5)-H(5A) 1.0000
C(6)-H(6A) 0.9900
C(6)-H(6B) 0.9900
C(7)-C(8) 1.537(2)
C(7)-H(7A) 0.9900
C(7)-H(7B) 0.9900
C(8)-C(9) 1.528(3)
C(8)-C(10) 1.529(3)
C(8)-H(8A) 1.0000
C(9)-H(9A) 0.9900
C(9)-H(9B) 0.9900
C(10)-H(10A) 0.9900
C(10)-H(10B) 0.9900
C(11)-C(12) 1.519(2)
C(11)-C(18) 1.544(3)
C(11)-H(11A) 1.0000
C(12)-C(17) 1.392(2)
C(12)-C(13) 1.393(2)
C(13)-C(14) 1.388(2)
C(13)-H(13A) 0.9500
C(14)-C(15) 1.379(3)
C(14)-H(14A) 0.9500
C(15)-C(16) 1.385(2)
C(16)-C(17) 1.381(2)
C(16)-H(16A) 0.9500
C(17)-H(17A) 0.9500
C(18)-C(19) 1.535(4)
C(18)-C(22) 1.537(4)
C(18)-C(22') 1.554(7)
C(18)-C(19') 1.569(6)
C(18)-H(18A) 1.0000
C(18)-H(18B) 1.0000
Chapter 6. Experimental 227
C(19)-C(20) 1.301(8)
C(19)-H(19A) 0.9500
C(20)-C(21) 1.514(7)
C(20)-H(20A) 0.9500
C(21)-C(22) 1.537(8)
C(21)-H(21A) 0.9900
C(21)-H(21B) 0.9900
C(22)-H(22A) 0.9900
C(22)-H(22B) 0.9900
C(19')-C(20') 1.546(11)
C(19')-H(19B) 0.9900
C(19')-H(19C) 0.9900
C(20')-C(21') 1.487(9)
C(20')-H(20B) 0.9900
C(20')-H(20C) 0.9900
C(21')-C(22') 1.305(12)
C(21')-H(21C) 0.9500
C(22')-H(22C) 0.9500
C(11)-N(1)-C(1) 118.26(13)
C(11)-N(1)-H(1) 106.6
C(1)-N(1)-H(1) 105.1
N(1)-C(1)-C(7) 111.48(13)
N(1)-C(1)-C(6) 106.10(13)
C(7)-C(1)-C(6) 108.11(14)
N(1)-C(1)-C(2) 113.38(13)
C(7)-C(1)-C(2) 108.85(14)
C(6)-C(1)-C(2) 108.74(14)
C(3)-C(2)-C(1) 110.38(14)
C(3)-C(2)-H(2A) 109.6
C(1)-C(2)-H(2A) 109.6
C(3)-C(2)-H(2B) 109.6
C(1)-C(2)-H(2B) 109.6
H(2A)-C(2)-H(2B) 108.1
C(10)-C(3)-C(4) 110.15(16)
C(10)-C(3)-C(2) 108.96(15)
C(4)-C(3)-C(2) 109.42(16)
C(10)-C(3)-H(3A) 109.4
C(4)-C(3)-H(3A) 109.4
C(2)-C(3)-H(3A) 109.4
C(3)-C(4)-C(5) 109.28(15)
C(3)-C(4)-H(4A) 109.8
C(5)-C(4)-H(4A) 109.8
C(3)-C(4)-H(4B) 109.8
C(5)-C(4)-H(4B) 109.8
H(4A)-C(4)-H(4B) 108.3
C(6)-C(5)-C(9) 109.20(15)
C(6)-C(5)-C(4) 109.54(15)
C(9)-C(5)-C(4) 109.21(16)
C(6)-C(5)-H(5A) 109.6
C(9)-C(5)-H(5A) 109.6
C(4)-C(5)-H(5A) 109.6
C(5)-C(6)-C(1) 110.94(14)
C(5)-C(6)-H(6A) 109.5
C(1)-C(6)-H(6A) 109.5
C(5)-C(6)-H(6B) 109.5
C(1)-C(6)-H(6B) 109.5
Chapter 6. Experimental 228
H(6A)-C(6)-H(6B) 108.0
C(1)-C(7)-C(8) 109.90(14)
C(1)-C(7)-H(7A) 109.7
C(8)-C(7)-H(7A) 109.7
C(1)-C(7)-H(7B) 109.7
C(8)-C(7)-H(7B) 109.7
H(7A)-C(7)-H(7B) 108.2
C(9)-C(8)-C(10) 109.50(16)
C(9)-C(8)-C(7) 110.10(15)
C(10)-C(8)-C(7) 109.53(15)
C(9)-C(8)-H(8A) 109.2
C(10)-C(8)-H(8A) 109.2
C(7)-C(8)-H(8A) 109.2
C(8)-C(9)-C(5) 109.23(15)
C(8)-C(9)-H(9A) 109.8
C(5)-C(9)-H(9A) 109.8
C(8)-C(9)-H(9B) 109.8
C(5)-C(9)-H(9B) 109.8
H(9A)-C(9)-H(9B) 108.3
C(3)-C(10)-C(8) 109.38(15)
C(3)-C(10)-H(10A) 109.8
C(8)-C(10)-H(10A) 109.8
C(3)-C(10)-H(10B) 109.8
C(8)-C(10)-H(10B) 109.8
H(10A)-C(10)-H(10B) 108.2
N(1)-C(11)-C(12) 110.81(14)
N(1)-C(11)-C(18) 108.52(14)
C(12)-C(11)-C(18) 110.90(14)
N(1)-C(11)-H(11A) 108.9
C(12)-C(11)-H(11A) 108.9
C(18)-C(11)-H(11A) 108.9
C(17)-C(12)-C(13) 118.51(16)
C(17)-C(12)-C(11) 120.50(15)
C(13)-C(12)-C(11) 120.99(15)
C(14)-C(13)-C(12) 121.09(16)
C(14)-C(13)-H(13A) 119.5
C(12)-C(13)-H(13A) 119.5
C(15)-C(14)-C(13) 118.94(16)
C(15)-C(14)-H(14A) 120.5
C(13)-C(14)-H(14A) 120.5
C(14)-C(15)-C(16) 121.21(16)
C(14)-C(15)-Cl(1) 119.49(14)
C(16)-C(15)-Cl(1) 119.30(14)
C(17)-C(16)-C(15) 119.23(16)
C(17)-C(16)-H(16A) 120.4
C(15)-C(16)-H(16A) 120.4
C(16)-C(17)-C(12) 121.01(16)
C(16)-C(17)-H(17A) 119.5
C(12)-C(17)-H(17A) 119.5
C(19)-C(18)-C(22) 102.2(5)
C(19)-C(18)-C(11) 117.0(4)
C(22)-C(18)-C(11) 120.1(4)
C(19)-C(18)-C(22') 106.2(6)
C(22)-C(18)-C(22') 16.1(4)
C(11)-C(18)-C(22') 105.4(4)
C(19)-C(18)-C(19') 17.2(3)
Chapter 6. Experimental 229
C(22)-C(18)-C(19') 99.2(6)
C(11)-C(18)-C(19') 105.7(4)
C(22')-C(18)-C(19') 98.5(5)
C(19)-C(18)-H(18A) 105.4
C(22)-C(18)-H(18A) 105.4
C(11)-C(18)-H(18A) 105.4
C(22')-C(18)-H(18A) 118.1
C(19')-C(18)-H(18A) 122.2
C(19)-C(18)-H(18B) 98.0
C(22)-C(18)-H(18B) 100.9
C(11)-C(18)-H(18B) 115.2
C(22')-C(18)-H(18B) 115.2
C(19')-C(18)-H(18B) 115.2
H(18A)-C(18)-H(18B) 10.0
C(20)-C(19)-C(18) 107.6(6)
C(20)-C(19)-H(19A) 126.2
C(18)-C(19)-H(19A) 126.2
C(19)-C(20)-C(21) 114.9(8)
C(19)-C(20)-H(20A) 122.5
C(21)-C(20)-H(20A) 122.5
C(20)-C(21)-C(22) 101.0(9)
C(20)-C(21)-H(21A) 111.6
C(22)-C(21)-H(21A) 111.6
C(20)-C(21)-H(21B) 111.6
C(22)-C(21)-H(21B) 111.6
H(21A)-C(21)-H(21B) 109.4
C(18)-C(22)-C(21) 103.7(7)
C(18)-C(22)-H(22A) 111.0
C(21)-C(22)-H(22A) 111.0
C(18)-C(22)-H(22B) 111.0
C(21)-C(22)-H(22B) 111.0
H(22A)-C(22)-H(22B) 109.0
C(20')-C(19')-C(18) 107.8(7)
C(20')-C(19')-H(19B) 110.1
C(18)-C(19')-H(19B) 110.1
C(20')-C(19')-H(19C) 110.1
C(18)-C(19')-H(19C) 110.1
H(19B)-C(19')-H(19C) 108.5
C(21')-C(20')-C(19') 100.3(10)
C(21')-C(20')-H(20B) 111.7
C(19')-C(20')-H(20B) 111.7
C(21')-C(20')-H(20C) 111.7
C(19')-C(20')-H(20C) 111.7
H(20B)-C(20')-H(20C) 109.5
C(22')-C(21')-C(20') 115.5(11)
C(22')-C(21')-H(21C) 122.2
C(20')-C(21')-H(21C) 122.2
C(21')-C(22')-C(18) 111.4(9)
C(21')-C(22')-H(22C) 124.3
C(18)-C(22')-H(22C) 124.3
Chapter 6. Experimental 230
Table 6.22: Torsion angles [°] for 16a.
C(11)-N(1)-C(1)-C(7) -66.29(18)
C(11)-N(1)-C(1)-C(6) 176.25(14)
C(11)-N(1)-C(1)-C(2) 56.96(19)
N(1)-C(1)-C(2)-C(3) 176.15(14)
C(7)-C(1)-C(2)-C(3) -59.16(19)
C(6)-C(1)-C(2)-C(3) 58.40(19)
C(1)-C(2)-C(3)-C(10) 60.2(2)
C(1)-C(2)-C(3)-C(4) -60.28(19)
C(10)-C(3)-C(4)-C(5) -59.41(19)
C(2)-C(3)-C(4)-C(5) 60.34(19)
C(3)-C(4)-C(5)-C(6) -59.83(19)
C(3)-C(4)-C(5)-C(9) 59.72(19)
C(9)-C(5)-C(6)-C(1) -60.22(19)
C(4)-C(5)-C(6)-C(1) 59.33(19)
N(1)-C(1)-C(6)-C(5) 179.57(14)
C(7)-C(1)-C(6)-C(5) 59.88(18)
C(2)-C(1)-C(6)-C(5) -58.15(18)
N(1)-C(1)-C(7)-C(8) -175.44(14)
C(6)-C(1)-C(7)-C(8) -59.20(18)
C(2)-C(1)-C(7)-C(8) 58.76(18)
C(1)-C(7)-C(8)-C(9) 60.35(19)
C(1)-C(7)-C(8)-C(10) -60.11(19)
C(10)-C(8)-C(9)-C(5) 60.84(19)
C(7)-C(8)-C(9)-C(5) -59.64(19)
C(6)-C(5)-C(9)-C(8) 59.1(2)
C(4)-C(5)-C(9)-C(8) -60.64(19)
C(4)-C(3)-C(10)-C(8) 59.5(2)
C(2)-C(3)-C(10)-C(8) -60.5(2)
C(9)-C(8)-C(10)-C(3) -60.0(2)
C(7)-C(8)-C(10)-C(3) 60.8(2)
C(1)-N(1)-C(11)-C(12) 85.98(17)
C(1)-N(1)-C(11)-C(18) -152.03(15)
N(1)-C(11)-C(12)-C(17) 45.0(2)
C(18)-C(11)-C(12)-C(17) -75.6(2)
N(1)-C(11)-C(12)-C(13) -135.84(16)
C(18)-C(11)-C(12)-C(13) 103.57(19)
C(17)-C(12)-C(13)-C(14) -0.8(3)
C(11)-C(12)-C(13)-C(14) -179.97(16)
C(12)-C(13)-C(14)-C(15) 0.3(3)
C(13)-C(14)-C(15)-C(16) 0.2(3)
C(13)-C(14)-C(15)-Cl(1) -179.35(14)
C(14)-C(15)-C(16)-C(17) -0.2(3)
Cl(1)-C(15)-C(16)-C(17) 179.40(14)
C(15)-C(16)-C(17)-C(12) -0.4(3)
C(13)-C(12)-C(17)-C(16) 0.8(3)
C(11)-C(12)-C(17)-C(16) -179.97(16)
N(1)-C(11)-C(18)-C(19) 54.4(4)
C(12)-C(11)-C(18)-C(19) 176.4(4)
N(1)-C(11)-C(18)-C(22) 179.2(5)
C(12)-C(11)-C(18)-C(22) -58.9(5)
N(1)-C(11)-C(18)-C(22') 172.1(5)
C(12)-C(11)-C(18)-C(22') -66.0(5)
N(1)-C(11)-C(18)-C(19') 68.4(4)
C(12)-C(11)-C(18)-C(19') -169.6(4)
Chapter 6. Experimental 231
C(22)-C(18)-C(19)-C(20) -26.6(10)
C(11)-C(18)-C(19)-C(20) 106.7(8)
C(22')-C(18)-C(19)-C(20) -10.5(11)
C(19')-C(18)-C(19)-C(20) 54.8(19)
C(18)-C(19)-C(20)-C(21) 10.1(13)
C(19)-C(20)-C(21)-C(22) 10.7(13)
C(19)-C(18)-C(22)-C(21) 32.2(9)
C(11)-C(18)-C(22)-C(21) -99.2(8)
C(22')-C(18)-C(22)-C(21) -74(3)
C(19')-C(18)-C(22)-C(21) 15.0(9)
C(20)-C(21)-C(22)-C(18) -26.3(10)
C(19)-C(18)-C(19')-C(20') -93(2)
C(22)-C(18)-C(19')-C(20') 8.6(8)
C(11)-C(18)-C(19')-C(20') 133.6(6)
C(22')-C(18)-C(19')-C(20') 24.9(9)
C(18)-C(19')-C(20')-C(21') -22.8(9)
C(19')-C(20')-C(21')-C(22') 11.5(14)
C(20')-C(21')-C(22')-C(18) 4.9(16)
C(19)-C(18)-C(22')-C(21') -2.7(13)
C(22)-C(18)-C(22')-C(21') 75(3)
C(11)-C(18)-C(22')-C(21') -127.4(10)
C(19')-C(18)-C(22')-C(21') -18.5(13)
Figure 6.12: Crystal packing of 16a viewed along the crystallographic a-axis.
Chapter 6. Experimental 232
6.6.7. Crystal data and structure refinement 16b
Empirical formula C23H30ClN
Formula weight 355.93
Temperature 100(2) K
Wavelength 0.71073 A°
Crystal system, space group Monoclinic, P21/c
Unit cell dimensions a = 9.6458(8) A° alpha = 90°
b = 15.645(2) A° beta = 91.295(6) °
c = 12.6055(7) A° gamma = 90 °
Volume 1901.8(3) A3
Z, Calculated density 4, 1.243 Mg/m3
Absorption coefficient 0.206 mm-1
F(000) 768
Crystal size 0.28 x 0.12 x 0.10 mm
Theta range for data collection 3.49 to 27.10 °
Limiting indices -12 ≤ h ≤ 12, -20 ≤ k ≤ 20, -16 ≤ l ≤ 16
Reflections collected / unique 47950 / 4184 [R(int) = 0.0611]
Completeness to theta = 27.10 99.8 %
Absorption correction Semi-empirical from equivalents
Max. and min. transmission 1.000 and 0.938
Refinement method Full-matrix least-squares on F2
Data / restraints / parameters 4184 / 163 / 320
Goodness-of-fit on F2 1.070
Final R indices [I>2sigma(I)] R1 = 0.0468, wR2 = 0.1023
R indices (all data) R1 = 0.0663, wR2 = 0.1100
Largest diff. peak and hole 0.375 and -0.325 e.A°-3
Chapter 6. Experimental 233
Table 6.23: Atomic coordinates ( x 104) and equivalent isotropic displacement parameters
(A2 x 103) for 16b. U(eq) is defined as one third of the trace of the orthogonalized Uij
tensor.
___________________________ _____________________________________ x y z U(eq) _______________________________ _________________________________ Cl(1) 8566(1) 1054(1) 9437(1) 32(1) N(1) 5102(2) 1281(1) 4762(1) 21(1) C(1) 4332(2) 2097(1) 4740(2) 19(1) C(2) 4513(2) 2536(1) 3666(2) 26(1) C(3) 3639(2) 3360(2) 3609(2) 33(1) C(4) 2110(3) 3135(2) 3723(2) 32(1) C(5) 1906(2) 2698(2) 4800(2) 30(1) C(6) 2794(2) 1884(1) 4866(2) 28(1) C(7) 4769(2) 2721(2) 5631(2) 25(1) C(8) 3892(2) 3537(2) 5565(2) 34(1) C(9) 2357(2) 3317(2) 5688(2) 34(1) C(10) 4098(3) 3966(2) 4495(2) 39(1) C(11) 6624(2) 1325(1) 4849(1) 22(1) C(12) 7156(2) 1250(1) 5993(1) 19(1) C(13) 8021(2) 1867(1) 6447(1) 23(1) C(14) 8474(2) 1811(1) 7500(1) 24(1) C(15) 8044(2) 1126(1) 8102(1) 22(1) C(16) 7202(2) 494(1) 7671(1) 23(1) C(17) 6765(2) 559(1) 6616(1) 22(1) C(18) 7325(2) 663(1) 4129(1) 27(1) C(19) 6799(4) 814(2) 2971(3) 21(1) C(20) 7538(5) 844(3) 2169(4) 28(1) C(21) 9131(11) 636(6) 2219(9) 30(1) C(22) 9538(4) 267(3) 3290(2) 41(1) C(23) 8847(12) 744(9) 4186(7) 34(2) C(19') 6771(14) 469(8) 3069(10) 37(2) C(20') 7710(14) 546(9) 2213(10) 41(2) C(21') 9050(30) 784(16) 2190(20) 32(2) C(22') 9721(7) 824(6) 3309(5) 26(2) C(23') 9000(30) 780(20) 4131(19) 35(3) N(1') 6223(14) 2097(7) 4390(12) 23(4) C(1') 4787(15) 2372(10) 4501(13) 17(5) C(2') 3723(16) 1869(11) 3850(14) 26(5) C(3') 2314(17) 2339(11) 3916(14) 29(5)
Chapter 6. Experimental 234
C(4') 1890(20) 2360(15) 5062(15) 30(7) C(5') 2962(19) 2886(12) 5733(15) 34(6) C(6') 4359(18) 2398(13) 5674(12) 16(5) C(7') 4948(17) 3287(10) 4074(16) 29(5) C(8') 3580(17) 3742(11) 4130(14) 15(4) C(9') 3120(30) 3773(12) 5288(15) 37(6) C(10') 2510(20) 3234(13) 3495(18) 26(8) ________________ ________________________________________________ Table 6.24: Bond lengths [A] and angles [°] for 16b.
Cl(1)-C(15) 1.7496(17)
N(1)-C(11) 1.471(2)
N(1)-C(1) 1.477(2)
N(1)-H(1A) 0.95(2)
N(1)-H(11B) 0.7078
C(1)-C(2) 1.532(3)
C(1)-C(6) 1.533(3)
C(1)-C(7) 1.540(3)
C(2)-C(3) 1.542(3)
C(2)-H(2A) 0.9900
C(2)-H(2B) 0.9900
C(3)-C(10) 1.523(4)
C(3)-C(4) 1.527(4)
C(3)-H(3A) 1.0000
C(4)-C(5) 1.537(4)
C(4)-H(4A) 0.9900
C(4)-H(4B) 0.9900
C(5)-C(9) 1.535(3)
C(5)-C(6) 1.536(3)
C(5)-H(5A) 1.0000
C(6)-H(6A) 0.9900
C(6)-H(6B) 0.9900
C(7)-C(8) 1.532(3)
C(7)-H(7A) 0.9900
C(7)-H(7B) 0.9900
C(8)-C(10) 1.524(4)
C(8)-C(9) 1.531(3)
C(8)-H(8A) 1.0000
C(9)-H(9A) 0.9900
C(9)-H(9B) 0.9900
C(10)-H(10A) 0.9900
C(10)-H(10B) 0.9900
C(11)-N(1') 1.392(9)
C(11)-C(12) 1.524(2)
C(11)-C(18) 1.543(2)
C(11)-H(11A) 1.0000
C(11)-H(11B) 1.0000
C(12)-C(13) 1.390(3)
Chapter 6. Experimental 235
C(12)-C(17) 1.393(2)
C(13)-C(14) 1.391(2)
C(13)-H(13A) 0.9500
C(14)-C(15) 1.382(3)
C(14)-H(14A) 0.9500
C(15)-C(16) 1.383(3)
C(16)-C(17) 1.390(2)
C(16)-H(16A) 0.9500
C(17)-H(17A) 0.9500
C(18)-C(19') 1.460(13)
C(18)-C(23) 1.474(12)
C(18)-C(19) 1.552(5)
C(18)-C(23') 1.63(3)
C(18)-H(18A) 1.0000
C(18)-H(18B) 1.0000
C(19)-C(20) 1.252(6)
C(19)-H(19A) 0.9500
C(20)-C(21) 1.571(12)
C(20)-H(20A) 0.9500
C(21)-C(22) 1.513(11)
C(21)-H(21A) 0.9900
C(21)-H(21B) 0.9900
C(22)-C(23) 1.520(9)
C(22)-H(22A) 0.9900
C(22)-H(22B) 0.9900
C(23)-H(23A) 0.9900
C(23)-H(23B) 0.9900
C(19')-C(20') 1.430(14)
C(19')-H(19B) 0.9900
C(19')-H(19C) 0.9900
C(20')-C(21') 1.34(3)
C(20')-H(20B) 0.9900
C(20')-H(20C) 0.9900
C(21')-C(22') 1.55(3)
C(21')-H(21C) 0.9900
C(21')-H(21D) 0.9900
C(22')-C(23') 1.261(18)
C(22')-H(22C) 0.9500
C(23')-H(23C) 0.9500
N(1')-C(1') 1.460(15)
N(1')-H(1'A) 0.8800
C(1')-C(2') 1.520(16)
C(1')-C(7') 1.538(17)
C(1')-C(6') 1.544(16)
C(2')-C(3') 1.549(16)
C(2')-H(2'A) 0.9900
C(2')-H(2'B) 0.9900
C(3')-C(4') 1.509(17)
C(3')-C(10') 1.510(17)
C(3')-H(3'A) 1.0000
C(4')-C(5') 1.554(18)
C(4')-H(4'A) 0.9900
C(4')-H(4'B) 0.9900
C(5')-C(9') 1.507(17)
C(5')-C(6') 1.551(17)
C(5')-H(5'A) 1.0000
Chapter 6. Experimental 236
C(6')-H(6'A) 0.9900
C(6')-H(6'B) 0.9900
C(7')-C(8') 1.503(16)
C(7')-H(7'A) 0.9900
C(7')-H(7'B) 0.9900
C(8')-C(10') 1.520(18)
C(8')-C(9') 1.535(17)
C(8')-H(8'A) 1.0000
C(9')-H(9'A) 0.9900
C(9')-H(9'B) 0.9900
C(10')-H(10C) 0.9900
C(10')-H(10D) 0.9900
C(11)-N(1)-C(1) 117.49(16)
C(11)-N(1)-H(1A) 107.0(14)
C(1)-N(1)-H(1A) 109.6(13)
C(11)-N(1)-H(11B) 36.9
C(1)-N(1)-H(11B) 149.4
H(1A)-N(1)-H(11B) 75.9
N(1)-C(1)-C(2) 109.70(15)
N(1)-C(1)-C(6) 107.30(17)
C(2)-C(1)-C(6) 108.59(16)
N(1)-C(1)-C(7) 113.90(16)
C(2)-C(1)-C(7) 109.03(19)
C(6)-C(1)-C(7) 108.18(17)
C(1)-C(2)-C(3) 110.07(16)
C(1)-C(2)-H(2A) 109.6
C(3)-C(2)-H(2A) 109.6
C(1)-C(2)-H(2B) 109.6
C(3)-C(2)-H(2B) 109.6
H(2A)-C(2)-H(2B) 108.2
C(10)-C(3)-C(4) 109.9(2)
C(10)-C(3)-C(2) 109.69(18)
C(4)-C(3)-C(2) 109.3(2)
C(10)-C(3)-H(3A) 109.3
C(4)-C(3)-H(3A) 109.3
C(2)-C(3)-H(3A) 109.3
C(3)-C(4)-C(5) 109.24(18)
C(3)-C(4)-H(4A) 109.8
C(5)-C(4)-H(4A) 109.8
C(3)-C(4)-H(4B) 109.8
C(5)-C(4)-H(4B) 109.8
H(4A)-C(4)-H(4B) 108.3
C(9)-C(5)-C(6) 109.57(19)
C(9)-C(5)-C(4) 108.9(2)
C(6)-C(5)-C(4) 109.49(19)
C(9)-C(5)-H(5A) 109.6
C(6)-C(5)-H(5A) 109.6
C(4)-C(5)-H(5A) 109.6
C(1)-C(6)-C(5) 110.72(18)
C(1)-C(6)-H(6A) 109.5
C(5)-C(6)-H(6A) 109.5
C(1)-C(6)-H(6B) 109.5
C(5)-C(6)-H(6B) 109.5
H(6A)-C(6)-H(6B) 108.1
C(8)-C(7)-C(1) 110.27(17)
C(8)-C(7)-H(7A) 109.6
Chapter 6. Experimental 237
C(1)-C(7)-H(7A) 109.6
C(8)-C(7)-H(7B) 109.6
C(1)-C(7)-H(7B) 109.6
H(7A)-C(7)-H(7B) 108.1
C(10)-C(8)-C(9) 109.6(2)
C(10)-C(8)-C(7) 109.44(18)
C(9)-C(8)-C(7) 110.0(2)
C(10)-C(8)-H(8A) 109.3
C(9)-C(8)-H(8A) 109.3
C(7)-C(8)-H(8A) 109.3
C(8)-C(9)-C(5) 109.09(17)
C(8)-C(9)-H(9A) 109.9
C(5)-C(9)-H(9A) 109.9
C(8)-C(9)-H(9B) 109.9
C(5)-C(9)-H(9B) 109.9
H(9A)-C(9)-H(9B) 108.3
C(3)-C(10)-C(8) 109.4(2)
C(3)-C(10)-H(10A) 109.8
C(8)-C(10)-H(10A) 109.8
C(3)-C(10)-H(10B) 109.8
C(8)-C(10)-H(10B) 109.8
H(10A)-C(10)-H(10B) 108.2
N(1')-C(11)-N(1) 75.1(6)
N(1')-C(11)-C(12) 123.0(7)
N(1)-C(11)-C(12) 112.37(14)
N(1')-C(11)-C(18) 117.4(7)
N(1)-C(11)-C(18) 112.01(15)
C(12)-C(11)-C(18) 111.27(15)
N(1')-C(11)-H(11A) 32.0
N(1)-C(11)-H(11A) 106.9
C(12)-C(11)-H(11A) 106.9
C(18)-C(11)-H(11A) 106.9
N(1')-C(11)-H(11B) 100.2
N(1)-C(11)-H(11B) 25.2
C(12)-C(11)-H(11B) 99.4
C(18)-C(11)-H(11B) 99.4
H(11A)-C(11)-H(11B) 132.1
C(13)-C(12)-C(17) 118.32(16)
C(13)-C(12)-C(11) 121.49(16)
C(17)-C(12)-C(11) 120.18(16)
C(12)-C(13)-C(14) 121.46(17)
C(12)-C(13)-H(13A) 119.3
C(14)-C(13)-H(13A) 119.3
C(15)-C(14)-C(13) 118.75(17)
C(15)-C(14)-H(14A) 120.6
C(13)-C(14)-H(14A) 120.6
C(14)-C(15)-C(16) 121.33(16)
C(14)-C(15)-Cl(1) 119.71(14)
C(16)-C(15)-Cl(1) 118.96(14)
C(15)-C(16)-C(17) 119.05(16)
C(15)-C(16)-H(16A) 120.5
C(17)-C(16)-H(16A) 120.5
C(16)-C(17)-C(12) 121.06(17)
C(16)-C(17)-H(17A) 119.5
C(12)-C(17)-H(17A) 119.5
C(19')-C(18)-C(23) 114.0(6)
Chapter 6. Experimental 238
C(19')-C(18)-C(11) 121.4(6)
C(23)-C(18)-C(11) 111.3(5)
C(19')-C(18)-C(19) 20.9(4)
C(23)-C(18)-C(19) 109.7(4)
C(11)-C(18)-C(19) 108.2(2)
C(19')-C(18)-C(23') 111.6(9)
C(23)-C(18)-C(23') 3.3(14)
C(11)-C(18)-C(23') 111.7(11)
C(19)-C(18)-C(23') 106.7(9)
C(19')-C(18)-H(18A) 88.9
C(23)-C(18)-H(18A) 109.2
C(11)-C(18)-H(18A) 109.2
C(19)-C(18)-H(18A) 109.2
C(23')-C(18)-H(18A) 111.8
C(19')-C(18)-H(18B) 102.9
C(23)-C(18)-H(18B) 100.1
C(11)-C(18)-H(18B) 103.7
C(19)-C(18)-H(18B) 123.5
C(23')-C(18)-H(18B) 103.0
H(18A)-C(18)-H(18B) 14.4
C(20)-C(19)-C(18) 125.8(4)
C(20)-C(19)-H(19A) 117.1
C(18)-C(19)-H(19A) 117.1
C(19)-C(20)-C(21) 122.3(6)
C(19)-C(20)-H(20A) 118.8
C(21)-C(20)-H(20A) 118.8
C(22)-C(21)-C(20) 110.4(7)
C(22)-C(21)-H(21A) 109.6
C(20)-C(21)-H(21A) 109.6
C(22)-C(21)-H(21B) 109.6
C(20)-C(21)-H(21B) 109.6
H(21A)-C(21)-H(21B) 108.1
C(21)-C(22)-C(23) 111.6(6)
C(21)-C(22)-H(22A) 109.3
C(23)-C(22)-H(22A) 109.3
C(21)-C(22)-H(22B) 109.3
C(23)-C(22)-H(22B) 109.3
H(22A)-C(22)-H(22B) 108.0
C(18)-C(23)-C(22) 112.0(8)
C(18)-C(23)-H(23A) 109.2
C(22)-C(23)-H(23A) 109.2
C(18)-C(23)-H(23B) 109.2
C(22)-C(23)-H(23B) 109.2
H(23A)-C(23)-H(23B) 107.9
C(20')-C(19')-C(18) 116.7(10)
C(20')-C(19')-H(19B) 108.1
C(18)-C(19')-H(19B) 108.1
C(20')-C(19')-H(19C) 108.1
C(18)-C(19')-H(19C) 108.1
H(19B)-C(19')-H(19C) 107.3
C(21')-C(20')-C(19') 131.8(18)
C(21')-C(20')-H(20B) 104.3
C(19')-C(20')-H(20B) 104.3
C(21')-C(20')-H(20C) 104.3
C(19')-C(20')-H(20C) 104.3
H(20B)-C(20')-H(20C) 105.6
Chapter 6. Experimental 239
C(20')-C(21')-C(22') 112(2)
C(20')-C(21')-H(21C) 109.2
C(22')-C(21')-H(21C) 109.2
C(20')-C(21')-H(21D) 109.2
C(22')-C(21')-H(21D) 109.2
H(21C)-C(21')-H(21D) 107.9
C(23')-C(22')-C(21') 121.5(18)
C(23')-C(22')-H(22C) 119.3
C(21')-C(22')-H(22C) 119.3
C(22')-C(23')-C(18) 125(2)
C(22')-C(23')-H(23C) 117.6
C(18)-C(23')-H(23C) 117.6
C(11)-N(1')-C(1') 118.1(11)
C(11)-N(1')-H(1'A) 121.0
C(1')-N(1')-H(1'A) 121.0
N(1')-C(1')-C(2') 115.2(13)
N(1')-C(1')-C(7') 97.8(11)
C(2')-C(1')-C(7') 111.4(14)
N(1')-C(1')-C(6') 112.0(12)
C(2')-C(1')-C(6') 109.8(14)
C(7')-C(1')-C(6') 110.0(13)
C(1')-C(2')-C(3') 107.9(12)
C(1')-C(2')-H(2'A) 110.1
C(3')-C(2')-H(2'A) 110.1
C(1')-C(2')-H(2'B) 110.1
C(3')-C(2')-H(2'B) 110.1
H(2'A)-C(2')-H(2'B) 108.4
C(4')-C(3')-C(10') 110.7(16)
C(4')-C(3')-C(2') 108.5(15)
C(10')-C(3')-C(2') 107.9(15)
C(4')-C(3')-H(3'A) 109.9
C(10')-C(3')-H(3'A) 109.9
C(2')-C(3')-H(3'A) 109.9
C(3')-C(4')-C(5') 110.1(14)
C(3')-C(4')-H(4'A) 109.6
C(5')-C(4')-H(4'A) 109.6
C(3')-C(4')-H(4'B) 109.6
C(5')-C(4')-H(4'B) 109.6
H(4'A)-C(4')-H(4'B) 108.2
C(9')-C(5')-C(6') 109.8(15)
C(9')-C(5')-C(4') 111.0(16)
C(6')-C(5')-C(4') 106.3(15)
C(9')-C(5')-H(5'A) 109.9
C(6')-C(5')-H(5'A) 109.9
C(4')-C(5')-H(5'A) 109.9
C(1')-C(6')-C(5') 108.1(12)
C(1')-C(6')-H(6'A) 110.1
C(5')-C(6')-H(6'A) 110.1
C(1')-C(6')-H(6'B) 110.1
C(5')-C(6')-H(6'B) 110.1
H(6'A)-C(6')-H(6'B) 108.4
C(8')-C(7')-C(1') 109.2(13)
C(8')-C(7')-H(7'A) 109.8
C(1')-C(7')-H(7'A) 109.8
Chapter 6. Experimental 240
C(8')-C(7')-H(7'B) 109.8
C(1')-C(7')-H(7'B) 109.8
H(7'A)-C(7')-H(7'B) 108.3
C(7')-C(8')-C(10') 108.5(16)
C(7')-C(8')-C(9') 109.3(14)
C(10')-C(8')-C(9') 108.1(15)
C(7')-C(8')-H(8'A) 110.3
C(10')-C(8')-H(8'A) 110.3
C(9')-C(8')-H(8'A) 110.3
C(5')-C(9')-C(8') 111.0(14)
C(5')-C(9')-H(9'A) 109.4
C(8')-C(9')-H(9'A) 109.4
C(5')-C(9')-H(9'B) 109.4
C(8')-C(9')-H(9'B) 109.4
H(9'A)-C(9')-H(9'B) 108.0
C(3')-C(10')-C(8') 112.8(15)
C(3')-C(10')-H(10C) 109.0
C(8')-C(10')-H(10C) 109.0
C(3')-C(10')-H(10D) 109.0
C(8')-C(10')-H(10D) 109.0
H(10C)-C(10')-H(10D) 107.8
Figure 6.13: Crystal packing viewed along the crystallographic a-axis for 16b.
Chapter 6. Experimental 241
6.6.8. Crystal data and structure refinement for 20
a) Hydrodimer structure from the cyclohexene addition reaction (20′)
Empirical formula C34H42Cl2N2
Formula weight 549.60
Temperature 100(2) K
Wavelength 0.71073 A°
Crystal system, space group Triclinic, P-1
Unit cell dimensions a = 6.4218(5) A° alpha = 84.03(2) °
b = 10.300(2) A° beta = 82.99(1)°
c = 10.942(1) A° gamma = 83.11(1)°
Volume 710.2(2) A°3
Z, Calculated density 1, 1.285 Mg/m3
Absorption coefficient 0.255 mm-1
F(000) 294
Crystal size 0.23 x 0.06 x 0.05 mm
Theta range for data collection 3.22 to 26.36°
Limiting indices -8 ≤ h ≤ 7, -12 ≤ k ≤ 12, -13 ≤ l ≤ 13
Reflections collected / unique 13053 / 2889 [R(int) = 0.0809]
Completeness to theta = 26.36 99.8 %
Absorption correction Semi-empirical from equivalents
Max. and min. transmission 1.000 and 0.923
Refinement method Full-matrix least-squares on F2
Data / restraints / parameters 2889 / 0 / 235
Goodness-of-fit on F2 1.034
Chapter 6. Experimental 242
Final R indices [I>2sigma(I)] R1 = 0.0522, wR2 = 0.1157
R indices (all data) R1 = 0.0864, wR2 = 0.1288
Largest diff. peak and hole 0.557 and -0.284 e.A°-3
_______________________________________________________________
x y z U(eq)
________________________________________________________________
Cl(1) -954(1) 6847(1) 9714(1) 28(1)
N(1) 3529(3) 6097(2) 3864(2) 17(1)
C(1) 3228(4) 7497(2) 3364(2) 13(1)
C(2) 3092(5) 7491(3) 1968(2) 19(1)
C(3) 2658(4) 8897(3) 1353(2) 21(1)
C(4) 4466(4) 9674(3) 1537(2) 21(1)
C(5) 4607(4) 9725(3) 2915(2) 19(1)
C(6) 5023(4) 8311(3) 3532(2) 18(1)
C(7) 1129(4) 8176(3) 3958(2) 17(1)
C(8) 714(4) 9585(3) 3336(2) 19(1)
C(9) 2518(4) 10370(3) 3507(3) 21(1)
C(10) 569(4) 9528(3) 1968(3) 21(1)
C(11) 4631(4) 5748(3) 4964(2) 21(1)
C(12) 3186(4) 6061(3) 6140(2) 21(1)
C(13) 1226(4) 5564(3) 6420(3) 24(1)
C(14) -48(5) 5784(3) 7522(3) 23(1)
C(15) 658(4) 6525(3) 8348(2) 21(1)
C(16) 2587(5) 7021(3) 8101(3) 25(1)
C(17) 3832(5) 6791(3) 6998(3) 24(1)
____________________________________________________________
Table 6.25: Atomic coordinates ( x 104) and equivalent isotropic displacement parameters
(A2 x 103) for 20′. U(eq) is defined as one third of the trace of the orthogonalized Uij
tensor.
Chapter 6. Experimental 243
Table 6.26: Bond lengths [A] and angles [°] for 20′.
Cl(1)-C(15) 1.749(3)
N(1)-C(11) 1.462(3)
N(1)-C(1) 1.487(3)
N(1)-H(1) 0.85(3)
C(1)-C(2) 1.541(3)
C(1)-C(6) 1.543(3)
C(1)-C(7) 1.544(3)
C(2)-C(3) 1.541(4)
C(2)-H(2A) 0.99(3)
C(2)-H(2B) 1.01(3)
C(3)-C(10) 1.529(4)
C(3)-C(4) 1.530(4)
C(3)-H(3) 0.96(3)
C(4)-C(5) 1.529(4)
C(4)-H(4A) 0.99(3)
C(4)-H(4B) 1.01(3)
C(5)-C(9) 1.524(4)
C(5)-C(6) 1.548(4)
C(5)-H(5) 0.93(3)
C(6)-H(6A) 1.01(3)
C(6)-H(6B) 1.04(3)
C(7)-C(8) 1.545(4)
C(7)-H(7A) 1.01(3)
C(7)-H(7B) 1.03(3)
C(8)-C(10) 1.519(4)
C(8)-C(9) 1.530(4)
C(8)-H(8) 0.93(3)
C(9)-H(9A) 0.93(3)
C(9)-H(9B) 0.98(3)
C(10)-H(10A) 0.93(3)
C(10)-H(10B) 1.03(3)
C(11)-C(12) 1.531(4)
C(11)-C(11) 1.553(5)
C(11)-H(11) 0.99(3)
C(12)-C(17) 1.391(4)
C(12)-C(13) 1.403(4)
C(13)-C(14) 1.394(4)
C(13)-H(13) 1.01(3)
C(14)-C(15) 1.390(4)
C(14)-H(14) 0.94(3)
C(15)-C(16) 1.382(4)
C(16)-C(17) 1.389(4)
C(16)-H(16) 0.94(3)
C(17)-H(17) 1.00(3)
C(11)-N(1)-C(1) 119.2(2)
C(11)-N(1)-H(1) 104(2)
C(1)-N(1)-H(1) 105(2)
N(1)-C(1)-C(2) 106.27(19)
N(1)-C(1)-C(6) 114.8(2)
C(2)-C(1)-C(6) 108.3(2)
N(1)-C(1)-C(7) 110.3(2)
C(2)-C(1)-C(7) 108.5(2)
C(6)-C(1)-C(7) 108.5(2)
C(1)-C(2)-C(3) 111.2(2)
Chapter 6. Experimental 244
C(1)-C(2)-H(2A) 108.1(17)
C(3)-C(2)-H(2A) 109.5(17)
C(1)-C(2)-H(2B) 111.1(16)
C(3)-C(2)-H(2B) 109.1(17)
H(2A)-C(2)-H(2B) 108(2)
C(10)-C(3)-C(4) 110.2(2)
C(10)-C(3)-C(2) 108.6(2)
C(4)-C(3)-C(2) 108.5(2)
C(10)-C(3)-H(3) 112.5(18)
C(4)-C(3)-H(3) 109.6(17)
C(2)-C(3)-H(3) 107.3(17)
C(5)-C(4)-C(3) 110.2(2)
C(5)-C(4)-H(4A) 110.0(17)
C(3)-C(4)-H(4A) 107.6(17)
C(5)-C(4)-H(4B) 111.0(16)
C(3)-C(4)-H(4B) 109.1(16)
H(4A)-C(4)-H(4B) 109(2)
C(9)-C(5)-C(4) 108.9(2)
C(9)-C(5)-C(6) 109.2(2)
C(4)-C(5)-C(6) 109.3(2)
C(9)-C(5)-H(5) 110.4(17)
C(4)-C(5)-H(5) 110.2(18)
C(6)-C(5)-H(5) 108.7(18)
C(1)-C(6)-C(5) 110.4(2)
C(1)-C(6)-H(6A) 108.3(16)
C(5)-C(6)-H(6A) 108.8(16)
C(1)-C(6)-H(6B) 109.8(15)
C(5)-C(6)-H(6B) 108.9(16)
H(6A)-C(6)-H(6B) 111(2)
C(1)-C(7)-C(8) 110.0(2)
C(1)-C(7)-H(7A) 107.6(16)
C(8)-C(7)-H(7A) 111.5(17)
C(1)-C(7)-H(7B) 110.5(16)
C(8)-C(7)-H(7B) 110.4(16)
H(7A)-C(7)-H(7B) 107(2)
C(10)-C(8)-C(9) 110.0(2)
C(10)-C(8)-C(7) 109.4(2)
C(9)-C(8)-C(7) 109.3(2)
C(10)-C(8)-H(8) 109.4(18)
C(9)-C(8)-H(8) 107.6(17)
C(7)-C(8)-H(8) 111.1(18)
C(5)-C(9)-C(8) 110.2(2)
C(5)-C(9)-H(9A) 110.5(19)
C(8)-C(9)-H(9A) 112.1(18)
C(5)-C(9)-H(9B) 108.0(17)
C(8)-C(9)-H(9B) 108.9(17)
H(9A)-C(9)-H(9B) 107(2)
C(8)-C(10)-C(3) 109.8(2)
C(8)-C(10)-H(10A) 111.5(18)
C(3)-C(10)-H(10A) 109.1(18)
C(8)-C(10)-H(10B) 112.1(16)
C(3)-C(10)-H(10B) 108.1(16)
H(10A)-C(10)-H(10B) 106(2)
N(1)-C(11)-C(12) 111.2(2)
Chapter 6. Experimental 245
N(1)-C(11)-C(11)1 108.3(3)
C(12)-C(11)-C(11)1 109.3(3)
N(1)-C(11)-H(11) 110.5(17)
C(12)-C(11)-H(11) 108.5(16)
C(11)1-C(11)-H(11) 109.0(18)
C(17)-C(12)-C(13) 117.9(3)
C(17)-C(12)-C(11) 120.8(2)
C(13)-C(12)-C(11) 121.3(2)
C(14)-C(13)-C(12) 121.6(3)
C(14)-C(13)-H(13) 117.0(17)
C(12)-C(13)-H(13) 121.3(17)
C(15)-C(14)-C(13) 118.4(3)
C(15)-C(14)-H(14) 119.6(18)
C(13)-C(14)-H(14) 122.0(18)
C(16)-C(15)-C(14) 121.2(3)
C(16)-C(15)-Cl(1) 119.8(2)
C(14)-C(15)-Cl(1) 118.9(2)
C(15)-C(16)-C(17) 119.4(3)
C(15)-C(16)-H(16) 119.3(19)
C(17)-C(16)-H(16) 121.3(19)
C(16)-C(17)-C(12) 121.4(3)
C(16)-C(17)-H(17) 118.3(17)
C(12)-C(17)-H(17) 120.3(17)
Chapter 6. Experimental 246
b) Hydrodimer structure from cyclopentene or α-pinene addition reaction (20)
Empirical formula C34H42Cl2N2
Formula weight 549.60
Temperature 100(2) K
Wavelength 0.71073 A°
Crystal system, space group Orthorhombic, Pna21
Unit cell dimensions a = 11.276(1) A° alpha = 90°
b = 12.100(1) A° beta = 90°
c = 20.803(2) A° gamma = 90°
Volume 2838.4(4) A3
Z, Calculated density 4, 1.286 Mg/m3
Absorption coefficient 0.255 mm-1
F(000) 1176
Crystal size 0.32 x 0.28 x 0.25 mm
Theta range for data collection 3.61 to 27.88°
Limiting indices -14 ≤ h ≤ 13, -15 ≤ k ≤ 15, -27 ≤ l ≤ 27
Reflections collected / unique 35712 / 6674 [R(int) = 0.0452]
Completeness to theta = 27.88 99.5 %
Absorption correction Semi-empirical from equivalents
Max. and min. transmission 1.000 and 0.968
Refinement method Full-matrix least-squares on F2
Data / restraints / parameters 6674 / 1 / 470
Goodness-of-fit on F2 1.025
Final R indices [I>2sigma(I)] R1 = 0.0390, wR2 = 0.0747
R indices (all data) R1 = 0.0611, wR2 = 0.0808
Absolute structure parameter 0.49(7)
Largest diff. peak and hole 0.348 and -0.270 e.A°-3
Chapter 6. Experimental 247
________________________________________________________________ x y z U(eq) _______________________________________________________________ Cl(1) 5086(1) 2167(1) 6495(1) 25(1) Cl(2) 9809(1) 2200(1) 8386(1) 23(1) N(1) 6626(2) 7622(2) 6918(1) 11(1) N(2) 8280(2) 7595(2) 7960(1) 12(1) C(1) 6805(2) 8145(2) 6281(2) 13(1) C(2) 8045(2) 8625(3) 6255(2) 14(1) C(3) 8235(2) 9259(3) 5617(2) 20(1) C(4) 7334(2) 10207(3) 5575(2) 18(1) C(5) 6079(2) 9733(3) 5589(2) 14(1) C(6) 5905(2) 9093(3) 6226(2) 15(1) C(7) 6623(2) 7359(3) 5707(2) 14(1) C(8) 6793(2) 7996(3) 5069(2) 15(1) C(9) 5899(2) 8932(3) 5021(2) 14(1) C(10) 8058(3) 8473(3) 5055(2) 21(1) C(11) 7289(2) 6617(2) 7074(2) 11(1) C(12) 6714(2) 5527(2) 6887(1) 9(1) C(13) 7390(2) 4666(3) 6627(2) 15(1) C(14) 6902(2) 3637(3) 6513(2) 15(1) C(15) 5712(2) 3452(3) 6643(2) 16(1) C(16) 5015(2) 4293(3) 6903(2) 13(1) C(17) 5523(2) 5326(2) 7022(2) 14(1) C(18) 8109(2) 8131(2) 8595(2) 9(1) C(19) 6833(2) 8609(3) 8672(2) 16(1) C(20) 6696(2) 9221(3) 9309(2) 17(1) C(21) 7567(2) 10186(3) 9334(2) 20(1) C(22) 8843(2) 9748(3) 9259(2) 17(1) C(23) 8973(2) 9118(3) 8624(2) 14(1) C(24) 8372(2) 7360(3) 9164(2) 12(1) C(25) 8236(2) 7981(3) 9801(2) 16(1) C(26) 9113(2) 8973(3) 9818(2) 17(1) C(27) 6963(3) 8422(3) 9866(2) 18(1) C(28) 7543(2) 6616(2) 7818(2) 10(1) C(29) 8130(2) 5543(3) 8015(1) 11(1) C(30) 7463(2) 4670(2) 8257(2) 11(1) C(31) 7964(2) 3637(2) 8371(2) 14(1) C(32) 9157(2) 3496(2) 8239(2) 13(1) C(33) 9851(2) 4348(3) 8013(2) 17(1) C(34) 9337(2) 5362(3) 7897(2) 13(1) ________________________________________________________________ Table 6.27: Atomic coordinates ( x 104) and equivalent isotropic displacement parameters
(A2 x 103) for 20. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.
Chapter 6. Experimental 248
Table 6.28: Bond lengths [A] and angles [°] for 20.
Cl(1)-C(15) 1.735(3)
Cl(2)-C(32) 1.758(3)
N(1)-C(11) 1.464(4)
N(1)-C(1) 1.483(4)
N(1)-H(1N) 0.86(2)
N(2)-C(28) 1.477(4)
N(2)-C(18) 1.484(4)
N(2)-H(2N) 0.88(2)
C(1)-C(2) 1.515(4)
C(1)-C(6) 1.537(4)
C(1)-C(7) 1.539(4)
C(2)-C(3) 1.548(5)
C(2)-H(2A) 1.03(3)
C(2)-H(2B) 1.00(3)
C(3)-C(10) 1.520(5)
C(3)-C(4) 1.535(4)
C(3)-H(3) 0.99(3)
C(4)-C(5) 1.527(4)
C(4)-H(4A) 0.91(3)
C(4)-H(4B) 1.06(3)
C(5)-C(9) 1.541(5)
C(5)-C(6) 1.548(4)
C(5)-H(5) 0.92(3)
C(6)-H(6A) 1.05(2)
C(6)-H(6B) 0.98(3)
C(7)-C(8) 1.547(5)
C(7)-H(7A) 0.91(3)
C(7)-H(7B) 0.97(3)
C(8)-C(9) 1.519(4)
C(8)-C(10) 1.539(4)
C(8)-H(8B) 0.95(3)
C(9)-H(9A) 0.99(3)
C(9)-H(9B) 0.90(4)
C(10)-H(10A) 0.99(3)
C(10)-H(10B) 0.99(4)
C(11)-C(12) 1.521(4)
C(11)-C(28) 1.572(2)
C(11)-H(1) 1.01(3)
C(12)-C(17) 1.394(3)
C(12)-C(13) 1.399(4)
C(13)-C(14) 1.382(4)
C(13)-H(13) 1.01(3)
C(14)-C(15) 1.387(4)
C(14)-H(14) 1.06(3)
C(15)-C(16) 1.395(4)
C(16)-C(17) 1.397(4)
C(16)-H(16) 0.95(3)
C(17)-H(17) 1.00(3)
C(18)-C(24) 1.536(4)
C(18)-C(23) 1.543(4)
C(18)-C(19) 1.559(3)
C(19)-C(20) 1.525(5)
Chapter 6. Experimental 249
C(19)-H(19A) 0.96(3)
C(19)-H(19B) 0.99(3)
C(20)-C(21) 1.527(4)
C(20)-C(27) 1.540(5)
C(20)-H(20) 0.99(3)
C(21)-C(22) 1.541(4)
C(21)-H(21A) 1.05(4)
C(21)-H(21B) 0.93(4)
C(22)-C(26) 1.525(5)
C(22)-C(23) 1.532(5)
C(22)-H(22) 1.04(3)
C(23)-H(23A) 1.04(2)
C(23)-H(23B) 0.98(3)
C(24)-C(25) 1.531(5)
C(24)-H(24A) 1.05(3)
C(24)-H(24B) 1.04(3)
C(25)-C(27) 1.537(4)
C(25)-C(26) 1.556(4)
C(25)-H(25) 1.00(3)
C(26)-H(26A) 1.02(3)
C(26)-H(26B) 1.07(3)
C(27)-H(27A) 0.97(4)
C(27)-H(27B) 1.00(3)
C(28)-C(29) 1.515(4)
C(28)-H(28) 0.98(3)
C(29)-C(30) 1.391(4)
C(29)-C(34) 1.401(3)
C(30)-C(31) 1.392(4)
C(30)-H(30) 0.92(2)
C(31)-C(32) 1.384(3)
C(31)-H(31) 0.85(3)
C(32)-C(33) 1.377(4)
C(33)-C(34) 1.379(5)
C(33)-H(33) 0.97(3)
C(34)-H(34) 0.90(3)
C(11)-N(1)-C(1) 118.9(2)
C(11)-N(1)-H(1N) 108.7(15)
C(1)-N(1)-H(1N) 111.9(15)
C(28)-N(2)-C(18) 117.1(2)
C(28)-N(2)-H(2N) 107.3(14)
C(18)-N(2)-H(2N) 104.1(14)
N(1)-C(1)-C(2) 108.8(2)
N(1)-C(1)-C(6) 107.1(2)
C(2)-C(1)-C(6) 108.7(2)
N(1)-C(1)-C(7) 114.3(2)
C(2)-C(1)-C(7) 109.4(2)
C(6)-C(1)-C(7) 108.4(2)
C(1)-C(2)-C(3) 110.4(2)
C(1)-C(2)-H(2A) 109.9(16)
C(3)-C(2)-H(2A) 102.2(19)
C(1)-C(2)-H(2B) 107.3(14)
C(3)-C(2)-H(2B) 109.2(17)
H(2A)-C(2)-H(2B) 118(2)
C(10)-C(3)-C(4) 109.7(3)
Chapter 6. Experimental 250
C(10)-C(3)-C(2) 109.4(3)
C(4)-C(3)-C(2) 109.0(3)
C(10)-C(3)-H(3) 109.9(17)
C(4)-C(3)-H(3) 112.0(18)
C(2)-C(3)-H(3) 106.8(18)
C(5)-C(4)-C(3) 109.4(2)
C(5)-C(4)-H(4A) 110.2(18)
C(3)-C(4)-H(4A) 110.3(19)
C(5)-C(4)-H(4B) 107.6(14)
C(3)-C(4)-H(4B) 112.0(14)
H(4A)-C(4)-H(4B) 107(3)
C(4)-C(5)-C(9) 110.1(3)
C(4)-C(5)-C(6) 108.7(2)
C(9)-C(5)-C(6) 108.9(3)
C(4)-C(5)-H(5) 109.7(18)
C(9)-C(5)-H(5) 110(2)
C(6)-C(5)-H(5) 110(2)
C(1)-C(6)-C(5) 110.7(2)
C(1)-C(6)-H(6A) 109.9(17)
C(5)-C(6)-H(6A) 109.2(17)
C(1)-C(6)-H(6B) 110.3(15)
C(5)-C(6)-H(6B) 111.7(17)
H(6A)-C(6)-H(6B) 105(2)
C(1)-C(7)-C(8) 109.9(3)
C(1)-C(7)-H(7A) 105(2)
C(8)-C(7)-H(7A) 111(2)
C(1)-C(7)-H(7B) 107(2)
C(17)-C(12)-C(11) 120.6(2)
C(13)-C(12)-C(11) 120.9(2)
C(8)-C(7)-H(7B) 110.4(19)
H(7A)-C(7)-H(7B) 113(3)
C(9)-C(8)-C(10) 109.5(3)
C(9)-C(8)-C(7) 110.2(3)
C(10)-C(8)-C(7) 108.6(2)
C(9)-C(8)-H(8B) 111.7(17)
C(10)-C(8)-H(8B) 106.8(15)
C(7)-C(8)-H(8B) 109.9(18)
C(8)-C(9)-C(5) 109.4(2)
C(8)-C(9)-H(9A) 108.4(18)
C(5)-C(9)-H(9A) 110.4(17)
C(8)-C(9)-H(9B) 111.1(19)
C(5)-C(9)-H(9B) 107(2)
H(9A)-C(9)-H(9B) 111(3)
C(3)-C(10)-C(8) 110.0(2)
C(3)-C(10)-H(10A) 107.1(16)
C(8)-C(10)-H(10A) 112.0(16)
C(3)-C(10)-H(10B) 106.8(18)
C(8)-C(10)-H(10B) 109.6(17)
H(10A)-C(10)-H(10B) 111(3)
N(1)-C(11)-C(12) 116.5(2)
N(1)-C(11)-C(28) 108.2(3)
C(12)-C(11)-C(28) 109.3(3)
N(1)-C(11)-H(1) 105.3(16)
C(12)-C(11)-H(1) 111.1(16)
C(28)-C(11)-H(1) 106.0(17)
C(17)-C(12)-C(13) 118.3(3)
Chapter 6. Experimental 251
C(14)-C(13)-C(12) 121.3(2)
C(14)-C(13)-H(13) 118.6(17)
C(12)-C(13)-H(13) 120.0(17)
C(13)-C(14)-C(15) 119.8(3)
C(13)-C(14)-H(14) 121.1(14)
C(15)-C(14)-H(14) 119.1(14)
C(14)-C(15)-C(16) 120.2(3)
C(14)-C(15)-Cl(1) 120.2(2)
C(16)-C(15)-Cl(1) 119.6(2)
C(15)-C(16)-C(17) 119.4(2)
C(15)-C(16)-H(16) 116.6(17)
C(17)-C(16)-H(16) 124.1(17)
C(12)-C(17)-C(16) 121.0(3)
C(12)-C(17)-H(17) 119.7(15)
C(16)-C(17)-H(17) 119.0(15)
N(2)-C(18)-C(24) 113.3(2)
N(2)-C(18)-C(23) 106.9(2)
C(24)-C(18)-C(23) 108.5(2)
N(2)-C(18)-C(19) 112.0(2)
C(24)-C(18)-C(19) 108.9(2)
C(23)-C(18)-C(19) 107.0(2)
C(20)-C(19)-C(18) 111.3(2)
C(20)-C(19)-H(19A) 114.9(19)
C(18)-C(19)-H(19A) 108.8(17)
C(20)-C(19)-H(19B) 111.7(18)
C(18)-C(19)-H(19B) 108.8(15)
H(19A)-C(19)-H(19B) 101(2)
C(19)-C(20)-C(21) 109.7(3)
C(19)-C(20)-C(27) 109.2(3)
C(21)-C(20)-C(27) 109.2(3)
C(19)-C(20)-H(20) 111.8(17)
C(21)-C(20)-H(20) 108.7(17)
C(27)-C(20)-H(20) 108.3(16)
C(20)-C(21)-C(22) 109.5(2)
C(20)-C(21)-H(21A) 110.9(17)
C(22)-C(21)-H(21A) 106.2(15)
C(20)-C(21)-H(21B) 105.7(17)
C(22)-C(21)-H(21B) 112.3(17)
H(21A)-C(21)-H(21B) 112(3)
C(26)-C(22)-C(23) 109.4(3)
C(26)-C(22)-C(21) 108.7(3)
C(23)-C(22)-C(21) 110.4(2)
C(26)-C(22)-H(22) 107.4(17)
C(23)-C(22)-H(22) 109.8(18)
C(21)-C(22)-H(22) 111.0(16)
C(22)-C(23)-C(18) 111.0(2)
C(22)-C(23)-H(23A) 110.4(17)
C(18)-C(23)-H(23A) 110.1(16)
C(22)-C(23)-H(23B) 106.7(16)
C(18)-C(23)-H(23B) 107.4(15)
H(23A)-C(23)-H(23B) 111(2)
C(25)-C(24)-C(18) 110.5(2)
C(25)-C(24)-H(24A) 111.6(18)
C(18)-C(24)-H(24A) 109.7(18)
C(25)-C(24)-H(24B) 109.2(18)
C(18)-C(24)-H(24B) 111.3(17)
Chapter 6. Experimental 252
H(24A)-C(24)-H(24B) 104(2)
C(24)-C(25)-C(27) 109.9(2)
C(24)-C(25)-C(26) 109.5(2)
C(27)-C(25)-C(26) 108.9(3)
C(24)-C(25)-H(25) 107.0(18)
C(27)-C(25)-H(25) 115.9(15)
C(26)-C(25)-H(25) 105.4(16)
C(22)-C(26)-C(25) 109.3(2)
C(22)-C(26)-H(26A) 109.4(17)
C(25)-C(26)-H(26A) 111.5(17)
C(22)-C(26)-H(26B) 114.6(18)
C(25)-C(26)-H(26B) 107.8(17)
H(26A)-C(26)-H(26B) 104(2)
C(25)-C(27)-C(20) 109.5(2)
C(25)-C(27)-H(27A) 109.2(17)
C(20)-C(27)-H(27A) 111.8(18)
C(25)-C(27)-H(27B) 108.2(15)
C(20)-C(27)-H(27B) 115.1(15)
H(27A)-C(27)-H(27B) 103(2)
N(2)-C(28)-C(29) 112.8(2)
N(2)-C(28)-C(11) 107.4(3)
C(29)-C(28)-C(11) 110.3(3)
N(2)-C(28)-H(28) 115.3(17)
C(29)-C(28)-H(28) 105.6(17)
C(11)-C(28)-H(28) 105.3(17)
C(30)-C(29)-C(34) 118.1(3)
C(30)-C(29)-C(28) 120.9(2)
C(34)-C(29)-C(28) 120.8(3)
C(29)-C(30)-C(31) 121.6(2)
C(29)-C(30)-H(30) 117.9(17)
C(31)-C(30)-H(30) 120.1(17)
C(32)-C(31)-C(30) 118.1(3)
C(32)-C(31)-H(31) 124.1(17)
C(30)-C(31)-H(31) 117.8(17)
C(33)-C(32)-C(31) 121.9(3)
C(33)-C(32)-Cl(2) 119.3(2)
C(31)-C(32)-Cl(2) 118.8(2)
C(32)-C(33)-C(34) 119.2(2)
C(32)-C(33)-H(33) 120.0(18)
C(34)-C(33)-H(33) 120.9(18)
C(33)-C(34)-C(29) 121.1(3)
C(33)-C(34)-H(34) 116.4(17)
C(29)-C(34)-H(34) 122.3(17)
Table 6.29: Hydrogen bonds for 20 [A and °]. _________________________________________________________________________
D-H...A d(D-H) d(H...A) d(D...A) <(DHA)
N(2)-H(2N)...N(1) 0.88(2) 2.36(2) 2.8589(19) 115.9(16)
_________________________________________________________________________
Chapter 6. Experimental 253
References:
[1] S. Gablenz, C. Damm, F. W. Müller, G. Israel, M. Rössel, A. Röder, H. Abicht, Sol.
State. Sci., 2001, 291.
[2] A. A. El-Emam, Chin. Pharm. J., 1990, 42, 309.
[3] R. D. Hinton, E. G. Janzen, J. Org. Chem. 1992, 57, 2646.
Curriculum Vitae
MÜGE ALDEMIR
Personal Details .
Date - Place of Birth 17/05/1978 - Izmir-TURKEY
Citizenship Turkish
Marital Status Unmaried
Parents Kemale Aldemir (Daysal), Mustafa Aldemir
Education .
since 01/2003 Ph.D.: Friedrich Alexander University of Erlangen-Nürnberg
Erlangen, GERMANY
Title of Thesis: “Metal Oxide Supported Cadmium Sulfide for
Photocatalytic Synthesis of Homoallylamines”
Supervisor: Prof. Dr. H. KISCH
02/2000 – 08/2001 M.Sc.: Ege University Institute of Natural Science,
Izmir, TURKEY
Department of Chemistry, Organic Chemistry (02/2000 – 07/2001)
Department of Solar Energy (cont. 07/2001 – 08/2001)
Title of Thesis: “Organic Photosynthesis Studies with
Photoactivated Metal Sulfides by Sunlight”
Supervisor: Prof. Dr. S. ICLI
10/1995 – 08/1999 B.Sc.: Ege University Faculty of Science Department of
Chemistry, Izmir, TURKEY Option: Technological Chemistry
Diploma Project: “Photocatalytic Hydrogen Production”
1983 –1994 Elementary and secondary school in Urla-Izmir, TURKEY
Professional and Research Experience .
03/2002 – 08/2002 Scientific Research, University of Erlangen-Nürnberg, GERMANY
In The Research Group of Prof. Dr. H. Kisch
10/2001 – 10/2002 Research Assistant, Ege University, Institute of Solar Energy
Izmir-TURKEY
08/1998 – 09/1998 Apprenticeship, PETKIM Petrochemistry Holding Inc.
Aliaga-TURKEY
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