Functional Aromatic Amino Ketones as UV/Vis probes for various liquid and solid environments

151 Pages·2003·1.54 MB·English

by  Sony Viao

Functional Aromatic Amino Ketones as UV/Vis probes for
various liquid and solid environments

von der Fakultät für Naturwissenschaften der Technischen Universität Chemnitz
genehmigte Dissertation zur Erlangung des akademischen Grades

doctor rerum naturalium
(Dr. rer. nat.)

vorgelegt von Master in Chemie Mohamed El-Sayed
geboren am 16.11.1966 in Port-Said, Ägypten

eingereicht am 20 Dezember 2002

Gutachter:
Prof. Dr. Stefan Spange, Technische Universität Chemnitz
Prof. Dr. Heinrich Lang, Technische Universität Chemnitz
Prof. Dr. Rainer Beckert, Friedrich-Schiller-Universität Jena

Tag der Verteidigung: 1 April 2003
Bibliographische Beschreibung und Referat 2
Bibliographische Beschreibung und Referat

El-Sayed, M.

Functional Aromatic Amino Ketones as UV/Vis probes for various liquid and solid
environments

Technische Universität Chemnitz-Zwickau, Fakultät für Naturwissenschaften, Dissertation,
2003, 140 Seiten, 141 Literaturzitate, 35 Abbildungen, 24 Tabellen, 14 Diagramme.

Zum gegenwärtigen Kenntnisstand bezüglich Solvatochromie, Sol-Gel Prozesse, und
der Synthese von Polyketonen wird eine kurze Einführung gegeben. Die Synthese-
konzeptionen funktionalisierter aromatischer Aminoketone werden vorgestellt. Die neuen
Verbindungen wurden mittels Elementaranalyse, Röntgenstrukturanalyse, und
spektroskopischen (NMR, UV/Vis, MS) Methoden aufgeklärt. Im Mittelpunkt der
Untersuchungen steht die Untersuchung des Einflusses von unterschiedlichen Medien
(Lösungmittel, Oberflächen, Sol-Gel Materialien und Nachbarnmoleküle im Kristall) auf die
Lage der UV/Vis-Absorptionsmaxima verschiedener aromatischer Aminoketone. Die
Ergebnisse der Untersuchungen liefern Informationen in Bezug auf der spezifische
Solvotationsvermögen, die Polarität von Feststoffoberflächen, der Einfluss funktionaler
Gruppen in aromatischen Aminoketonen auf die intermolekulare Wasserstoff-
brückenbindungen in Kristallen, und über die Natur der Gast-Host- Wechselwirkungen.
Auf der Basis von nucleophilen Substitutionsreaktionen wurden zwei verschiedene
Prozesse für die Synthese von Poly(benzophenone-co-piperazin) und der Kompositform
entwickelt. Molekulare Strukturen und Eigenschaften konnten durch Elementaranalyse,
mehrere spektroskopische (IR, Festkörper-NMR, UV/Vis, MALDI-TOF) Methoden,
Zetapotentialmessungen in wässriger Phase und thermogravimetrischen Bestimmungen
charakterisiert werden.

Aromatische Aminoketonen, Aerosil 300, Sol-Gel-Prozess, Ormosile, Hybridmaterialien,
Solvatochromie, Acidität, Basizität, Dipolarität/Polarisierbarkeit, intermolekulare
Wasserstoffbrückenbindungen, Poly(benzophenone-co-piperazine).
Contents 3
Table of contents 3
List of publications 5
Acknowledgement 6
Symbols and abbreviations 7
I General part 10
1.1 Introduction 10
1.2 Solvatochromism 11
1.2.1 Aromatic amino ketones 12
1.2.2 Related compound 16
1.3 Sol-gel process 18
1.4 Aromatic amino ketone polymers 21
II Aim of this work 23
III Results and discussion 25
3.1 Aromatic amino ketones 25
3.1.1 UV/Vis absorption spectroscopy and linear solvation energy (LSE)
relationships 25
3.1.1.1 Solvent effects on the UV/Vis absorption spectra 25
3.1.1.2 Mathematical calculations based on LSE relationships 36
3.1.2 X-ray crystal structure analysis and powder reflectance UV/Vis
spectroscopy 52
3.1.2.1 Solid-state X-ray crystal structure analysis 52
3.1.2.2 UV/Vis diffuse reflectance spectra of the solid powders 63
3.1.3 Adsorption of aromatic amino ketones on Aerosil 300 68
3.1.4 Sol-gel materials containing aromatic amino ketones 73
3.1.4.1 Physical entrapment in a microporous silica network 73
3.1.4.2 Chemical linking to the silica network 83
3.2 N-(2’-hydroxy-4’-dimethylaminobenzylidene)-4-nitroaniline [HDBN] 90
3.2.1 UV/Vis absorption spectroscopy of HDBN 90
3.2.2 X-ray crystal structure analysis and powder reflectance UV/Vis
spectroscopy of HDBN 96
3.2.3 Adsorption of HDBN on Aerosil 300 99
3.3 Poly(benzophenone co-piperazine) and its silica-composite 102
3.3.1 Syntheses and structure analysis 102
3.3.2 Characterization 110
Contents 4
3.3.2.1 Electrokinetic data 110
3.3.2.2 Thermal stability 112
3.3.2.3 N adsorption/desorption data 114
2
3.3.3 Solvatochromic analysis 115
IV Summary 119
V Experimental section 123
5.1 General considerations 123
5.1.1 Instruments 123
5.1.2 Working procedures 125
5.1.3 Correlation analysis 125
5.1.4 Starting materials 125
5.2. Synthetic part 126
5.2.1 Aromatic amino ketones by Friedel Craft acylation reaction 126
5.2.2 Aromatic amino ketones by nucleophilic aromatic substitution reaction 129
5.2.3 3-(4-Di(2-hydroxyethyl)amino)phenyl-1-(2-furyl)-2-propene-1-one 132
5.2.4 N-(2’-hydroxy-4’-dimethylaminobenzylidene)-4-nitroaniline 132
5.3 Preparation of sol-gel hybrid materials 133
5.3.1 Physical entrapment in a microporous silica network 133
5.3.2 Chemical linking to the silica network 134
5.4 Poly(benzophenone co-piperazine) and its composite form 137
5.4.1. Solution polymerization 137
5.4.2. Solid-state polymerization 137
5.5 Crystal structure analyses 137
VI References 142
List of publications 5
List of publications

Original contributions:

1. El-Sayed, M.; Müller, H.; Rheinwald, G.; Lang, H.; Spange, S.: Linear solvation
energy (LSE) correlations of the solvatochromic response and x-ray structure
analysis of hydrophilically N-substituted Michler’s Ketone Derivatives. J. Phys.
Org. Chem. 2001, 14, 247-255.
2. Zimmermann, Y.; El-Sayed, M.; Prause, S.; Spange, S.: The Solvent-Like Nature
of Silica Particles in Organic Solvents. Monatsh. Chem. 2001, 132, 1347-1361.
3. Spange, S.; El-Sayed, M.; Müller, H.; Rheinwald, G.; Lang, H.; Poppitz, W.:
Solid-state Structures of N-substituted Michler’s Ketones and their relation to
Solvatochromism. Eur. J. Org. Chem. 2002, 24, 4159-4168.
4. El-Sayed, M.; Müller, H.; Rheinwald, G.; Lang, H.; Spange, S.: UV/Vis
spectroscopic properties of N-(2’-hydroxy-4’-N,N-dimethyl-aminobenzylidene)-
4-nitroaniline in various solvents and solid environments. Monatsh. Chem. 2003,
134, 361-370.
5. El-Sayed, M.; Müller, H.; Rheinwald, G.; Lang, H.; Spange, S.:
Solvatochromism, Crystallochromism, and Solid State Structures of
Hydrophilically Functionalized Aromatic Amino Ketones containing Furan and
Thiophene Rings. Chem. Mat. 2003, 15, 746-754.

Poster:

1. El-Sayed, M.; Schmidt, C.; Spange, S.; Kricheldorf, H.: Hydrophilically
Functionalized Michler’s Ketone Derivatives as Polarity Probes for Different
solid Materials. Berliner Polymerntage 2000, Poster (P 64, page 127), Berlin, 9. -
11. October 2000.
Acknowledgement 6
Acknowledgement

The experimental part of this work was carried out in the laboratories of Prof. Dr.
Stefan Spange, Chemnitz University of Technology from July 1998 until April 2002.

First of all, I wish to express my deep thanks and gratitude to Prof. Dr. Stefan Spange,
who welcomed me in his research group, who introduced me into German life and who
suggested the point and successfully guided me through my studies.

I would like to thank Prof. Dr. Heinrich Lang very much for his scientific support in crystal
structure analyses, and his evaluation of this thesis.

I would also like to thank Dr. Gerd Rheinwald for X-ray intensity data collection.

My deepest thanks are also to Dr. Hardy Müller for his interest and continuous
encouragement.

I would like to thank staff members in our research group for their co-operation, friendship
by means which the daily work has always been a pleasure.

I want to express my deepest gratitude to my parents Kauther El-Gamel and Mohamed El-
Sayed, and to my sister Frial and to my brothers Ashraf and Ibrahim for their constant
support and understanding.

I extend my thanks to my wife Dr. Eng. Hanan Koutta and my daughters Mirna and Manar
for understanding my demanding work and long working hours.

Finally, I would like to thank the Germany Ministry of Education, the Fonds der Chemischen
Industrie, Frankfurt am Main and Chemnitz University of Technology for their financial
support.
Symbols and abbreviations 7
Symbols and abbreviations

δ chemical shift
β hydrogen-bond accepting capacity
α hydrogen-bond donating capacity
δ polarizability correction term
π* dipolarity/polarizability
δ2 solvent cohesive energy density
H
δ hildebrand solubility parameter
H
λ maximum wave length
max
ν maximum wave number
max
[M+] molecule-ion
a solvent-independent correlation coefficient of α
a.u. arbitrary units
b Solvent-independent correlation coefficient of β
b.p. boiling point
BBP 1,4-bis(4-benzoylphenyl)piperazine
BET brunauer-Emmett-Teller
BuOH 1-butanol
CH c-hexane
CP cross-polarization
d doublet
D two oxygen atoms and two alkyl group attached to silicon atom
DAFP 3-(4-di(2-hydroxyethyl)amino)phenyl-1-(2-furyl)-2-propene-1-one
DCE 1,2-dichloroethane
DCM dichloromethane
dd doublet of doublets
DEE diethyl ether
DEI desorption electron ionization
DeOH 1-decanol
DH Dollimore-Heal
DMAc N,N-dimethylacetamide
DMF N,N-dimethylformamide
DMSO dimethylsulfoxide
DPAB 4-dimethylamino-4’-[di(2-propyltriethoxysilylcarbamatoethyl)amino]-
benzophenone
Symbols and abbreviations 8
DPAF [4-di(2-propyltriethoxysilylcarbamatoethyl)amino]-2-furylmethanone
DPAT [4-di(2-propyltriethoxysilylcarbamatoethyl)amino]-2-thienylmethanone
DSC differential scanning calorimetry
EG ethane-1,2-diol
ESI electron spray ionization
EtOH ethanol
Exp. Sect. experimental section
F significance
Fig. figure
FT-IR Fourier transform-Infrared
Fur(OAc) [4-di(2-acetoxyethyl)aminophenyl]-2-furylmethanone
2
Fur(OH) [4-di(2-hydroxyethyl)aminophenyl]-2-furylmethanone
2
g gram
h hour
HBA hydrogen-bond accepting
HBD hydrogen-bond donating
HDBN N-(2’-hydroxy-4’-dimethylaminobenzylidene)-4-nitroaniline
HeOH 1-hexanol
HFP 1,1,1,3,3,3-hexafluoro-2-propanol
J coupling constant
LSE linear solvation energy
m.p. melting point
m/z mass/charge
MALDI-TOF matrix assisted laser desorption ionization time-of-flight
MAS magic angle spinning
MeOH methanol
MHz megahertz
MK 4,4’-bis-(dimethylamino)benzophenone, Michler’s Ketone
MK(mor) 4,4’-bis(morpholino)benzophenone
2
MK(NEt ) 4,4’-bis(diethylamino)benzophenone
2 2
MK(OAc) 4-dimethylamino-4’-[di(2-acetoxyethyl)amino]benzophenone
2
MK(OH) 4-dimethylamino-4’-[di(2-hydroxyethyl)amino]benzophenone
2
MK(pip) 4,4’-bis(piperidino)benzophenone
2
MK(pipaz) 4,4’-bis(piperazino)benzophenone
2
MK(pipazOH) 4,4’-bis[4-(2-hydroxyethyl)piperazino]benzophenone
2
MK(pipOEt) 4,4’-bis(4-ethoxycarbonylpiperazino)benzophenone
2
mmol millimole
Symbols and abbreviations 9
MS mass spectra
MTMOS methyltrimethoxysilane
N normal
n number of solvents
nm nano-meter
NMR nuclear magnetic resonance
OcOH 1-octanol
Ormosil organically modified silica
pm pico-meter
PrOH 1-propanol
PSD pore-size distribution
Q four oxygen atoms attached to silicon atom
r correlation coefficient
s solvent-independent correlation coefficient of π*
SD standard deviation
T three oxygen atoms and one alkyl group attached to silicon atom
t triplet
Tab. table
TCE 1,1,2,2-tetrachloroethane
TEOS tetraethylorthosilicate
TFE 2,2,2-trifluoroethanol
T glass transition temperature
g
TGA thermogravimetric analysis
Thi(OAc) [4-di(2-acetoxyethyl)aminophenyl]-2-thienylmethanone
2
Thi(OH) [4-di(2-hydroxyethyl)aminophenyl]-2-thienylmethanone
2
TMOS tetramethoxysilane
tol. toluene
UV/Vis ultraviolet/visible
General part 10
I. General part

1.1 Introduction

The color change of a compound induced by external influences, e. g. by solvents
(solvatochromism), applied stress (mechanochromism), salts (halochromisms) and/or
temperature (thermochromism) has been studied intensively over the last decades.1-9 In this
context, solvatochromic dyes have been established as empirical polarity indicators for
solvents, solvent mixtures and solution of several solutes in various liquids.1,10-13 This
empirically derived concept for volume effects has been also widespread applied to evaluate
the internal and external polarities of surfaces of macro-molecular and related materials.14-24
In this sense, the term surface polarity is an argument often used in interpreting experimental
results obtained from Chromatography22 and heterogeneous catalysis.25 The effect of solid
matrix is important, because many compounds (such as dyes, stabilizers and others) are
applied as components of a more complex system in the solid phase. Therefore it is important
to evaluate the medium effect for these systems as well.
The solvatochromic effects of rigid matrices are complex and as yet less understood as
compared with solvents. It is important to take into account not only the matrix itself but its
mode of preparation and the way in which the solute has been incorporated into the matrix.
To date, no generally agreed upon definition of the term surface polarity has emerged. In the
broadest and most general sense the surface polarity can be viewed as the sum of all
interactive forces between an adsorbed molecule and the occupied surface site or sites. This
definition is based on the related interpretation of the term solvent polarity.1,26 Most solvent
polarity scales are empirical and are based on kinetic, thermodynamic, or spectroscopic data
relating to certain reference reactions.1 Significantly, different empirical solvent polarity
scales have been shown to correlate well with each other, pointing to the existence of an
underlying common feature.1
Since, a chromophor is covalently functionalized by a polar group or another suitable
moiety for molecular recognition in its periphery, manifold influences on the UV/Vis spectra
can result from the intermolecular interaction in the solid-state (crystal) or in molecular
aggregates of the dye.27-31 Thus, quantum size effects have been observed for organic nano-
crystals29 and carotenoid dye nano-particles.28 However, two different influences, the supra-
molecular structure and quantity of accumulated dye molecules in the nanocrystal seem of
importance for the resulting UV/Vis spectroscopic property. Because both influences are