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Publié par | johannes_gutenberg-universitat_mainz |
Publié le | 01 janvier 2006 |
Nombre de lectures | 32 |
Langue | Deutsch |
Poids de l'ouvrage | 10 Mo |
Extrait
Synthetical Engineering of Supramolecular
Properties of Large Polycyclic Aromatic
Hydrocarbons
Dissertation zur Erlangung des Grades
“Doktor der Naturwissenschaften”
am Fachbereich Chemie, Pharmazie und Geowissenschaften der
Johannes Gutenberg-Universität in Mainz
Daniel Wasserfallen
geb. in Bern, Schweiz
Mainz 2006
Dekan:
1. Berichterstatter:
2.
Tag der mündlichen Prüfung:
i
ii
Die vorliegende Arbeit wurde in der Zeit vom März 2002 bis November 2005 im Max-
Planck-Institut für Polymerforschung unter der Leitung von Herrn Prof. Dr. K. Müllen
durchgeführt.
Ich danke Herrn Prof. Dr. K. Müllen sowohl für seine wissenschaftliche und persönliche
Unterstützung als auch für seine stetige Diskussionsbereitschaft.
iii
iv
Dedicated to my mother
"Die Schwierigkeiten scheinen nur da zu sein, um überwunden zu werden."
Hoffmann von Fallersleben (1798-1874)
v
vi Contents
1 Introduction..............................................................................................................1
1.1 Benzene and Aromaticity................................................................................... 1
1.2 Polycyclic Aromatic Hydrocarbons...................................................................2
1.3 The "Aromatic Sextet" and Fully Benzenoid PAHs.......................................... 3
1.4 Synthesis of PAHs ............................................................................................. 6
1.4.1 Cyclotrimerization of Diphenylacetylenes ................................................ 8
1.4.2 Intramolecular Diels-Alder Reaction......................................................... 9
1.4.3 Interme 9
1.5 Supramolecular Properties of PAHs................................................................ 11
1.5.1 Discotic Liquid Crystals .......................................................................... 12
1.5.2 Monolayers of PAHs...............................................................................16
1.5.3 Intracolumnar Charge Carrier Transport ................................................. 18
1.7 Devices Based on Discotic Organic Materials ................................................ 20
1.8 References........................................................................................................22
2 Motivations and Objectives .................................................................................. 29
2.1 References31
3 Influence of Hydrogen-Bonds on the Supra-molecular Properties of Hexa-
peri-hexabenzo-coronenes ..................................................................................... 33
3.1 Hydrogen-bonds .............................................................................................. 34
3.2 Desymmetrized HBCs36
3.3 Engineering the Properties of HBC via Hydrogen-Bonding ........................... 37
3.3.1 Synthesis of Carboxy-functionalized HBCs............................................ 38
3.3.2 Covalently Linked Dyads.................................................... 42
3.3.3 Bulk Properties of Carboxy-functionalized HBCs and Dyads ................ 43
3.3.3.1 Differential Scaning Calorimetry (DSC) 43
3.3.3.2 2D-WAXS..........................................................................................44
3.3.3.3 Solid-State NMR of Carboxy-functionalized HBCs .......................... 50
3.3.4 Properties on Surfaces ............................................................................. 53
3.3.5 Discussion................................................................................................55
3.4 Inducing processability....................................................................................59
3.4.1 Synthesis..................................................................................................60
3.4.2 Bulk Properties........................................................................................62
3.4.2.1 DSC.....................................................................................................
3.4.2.2 2D-WAXS..........................................................................................63
3.4.3 Discussion66
3.4.4 Conclusions..............................................................................................69
3.6 References........................................................................................................
4 "Supernaphthalene"75
4.1 Synthesis .............................................................................................................. 78
4.1.1 2,2'-Diethinylbiphenyl.............................................................................78
4.1.2 Tetraphenylcyclopentadienone Derivatives............................................. 81
4.1.3 Intramolecular Cyclodehydrogenation....................................................84
4.1.3.1 C72-(C ) .......................................................................................... 86 8,2 8
4.1.3.2 ) ........................................................................................... 88 12 8
4.1.3.3 C72-(Ph-C ) ..................................................................................... 89 12 8
vii 4.2 Closer Investigation on C72-(C ) ......................................................................91 12 8
4.2.1 UV/vis ......................................................................................................91
4.2.2 HPLC........................................................................................................92
4.2.3 Photoluminescence Experiments..............................................................95
4.2.4 Polarized Optical Microscopy..................................................................97
4.2.5 2D-WAXS................................................................................................98
4.2.6 Conclusions ..............................................................................................99
4.3 Verification of the MALDI-TOF MS Data ........................................................100
4.3.1 C72-(C ) ...............................................................................................100 12 8
4.3.2 Investigations on Other Extended PAHs................................................106
4.3.3 Discussion109
4.3.4 Conclusions............................................................................................117
4.4 Investigations on Workup Procedures................................................................118
4.4.1 Preparative Column Chromatography....................................................118
4.4.2 Influencing the Retention Times ............................................................119
4.5 Influencing the Electronic and Solubility Properties of the Oligophenylene
Precursor.............................................................................................................124
4.5.1 Removal of Alkyl Side-Chains ..............................................................124
4.5.2 Changing the Oligophenylene Substitution Pattern ...............................128
4.5.3 Conclusions............................................................................................142
4.6 Preplanarization of the Oligophenylene Precursor at the Outer Rim................143
4.6.1 C74, C76, C76-(t-Bu).............................................................................143
4.6.2 Specific Synthesis of Panels...................................................................151
4.7 Preplanarization in the Center of the Oligophenylene Precursor ......................158
4.7.1 Inducing Solubility by Distortion of the Aromatic Core Component
and Bulky Substituents ...........................................................................160
4.7.2 C72-(C ) -(t-Bu) ..................................................................................163 12 8 2
4.7.2.1 Synthesis............................................................................................164
4.7.2.2 MALDI-TOF MS ..............................................................................166
14.7.2.3 H NMR Spectroscopy......................................................................167
4.7.2.4 Electronic Spectroscopy....................................................................168
4.7.3 Improving the Solubility Properties by Bulky Alkyl Substituents.........17