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From Pyrene to Large Polycyclic Aromatic Hydrocarbons From Pyrene to Large Polycyclic Aromatic Hydrocarbons Dissertation zur Erlangung des Grades “Doktor der Naturwissenschaften” am Fachbereich Chemie, Pharmazie und Geowissenschaften der Johannes Gutenberg-Universität Mainz Yulia Fogel geboren in Moscow Mainz, 2007 Dekan: 1. Berichterstatter: 2. Berichterstatter: Tag der mündlichen Prüfung: Herr Prof. Dr. K. Müllen, unter dessen Anleitung ich die vorliegende Arbeit am Max-Planck Institut für Polymerforschung in Mainz in der Zeit von Februar 2003 bis Mai 2006 angefertigt habe, danke ich für seine wissenschaftliche und persönliche Unterstützung sowie seine ständig Diskussionsbereitschaft. Dedicated to my family and all my friends Index of Abbreviations 2D-WAXS two-dimensional wide-angle X-ray scattering AFM atomic force microscopy bd doublet broad (NMR) bipy bipyridyl bs broad singlet (NMR) cal. calculated d doublet (NMR) DBU 1,8-Diazabicyclo[5,4,0]undec-7-en DCM dichloromethane DCTB trans-2-[3-(4-tert-butylphenyl)-2-methyl-2-propenylidene] malononitrile DMF N,N-dimethylformamide DSC differential scanning calorimetry FD field desorption FET field-effect transistor FVP flash vacuum pyrolyis GPC gel permeation chromatography h hour HBC hexa-peri-hexabenzocoronene HOMO highest occupied molecular orbital HR-TEM high-resolution transmission electron microscopy J coupling constant / Hz LC liquid crystal LED light emitting diode LUMO lowest unoccupied molecular orbital m multiplett (NMR) M+ molecular ion MALDI-TOF matrix-assisted laser desorption/ionization time-of-flight Me methyl min minute MS mass spectrometry NMR nuclear magnetic resonance PAH polycyclic aromatic hydrocarbon PE petroleum ether, low boiling Ph phenyl PL photoluminescence PLE photoluminescence excitation POM polarization optical microscopy ppm parts per million s singlet (NMR) SEM scanning electron microscopy t triplet (NMR) tBu tert-butyl TBO tetrabenzo[bc,ef,hi,uv]ovalene TEM transmission electron microscopy THF tetrahydrofuran TGA thermo-gravimetry analysis TLC thin layer chromatography UV/vis UV-visible absorption spectroscopy Table of Content FROM PYRENE TO LARGE POLYCYCLIC AROMATIC HYDROCARBONS................ 1 1 INTRODUCTION ................................................................................................................ 2 1.1 Polycyclic Aromatic Hydrocarbons.................................................................... 2 1.2 Synthesis of PAH................................................................................................ 4 1.2.1 Diels-Alder Cycloaddition.......................................................................... 4 1.2.2 Friedel-Crafts-type Reactions ..................................................................... 5 1.2.3 Extrusion of Heteroatoms ........................................................................... 6 1.2.4 Photocyclization.......................................................................................... 7 1.2.5 Flash Vacuum Pyrolysis (Thermolysis)...................................................... 7 1.2.6 Scholl-Cyclodehydrogenation..................................................................... 8 1.3 Supramolecular Organization ............................................................................. 9 1.4 Extended PAHs................................................................................................. 11 1.5 Metal-PAH complexes...................................................................................... 12 1.6 Motivation and Objectives................................................................................ 13 1.7 References......................................................................................................... 15 2 FROM PYRENE TOWARDS GRAPHITE RIBBONS .................................................. 20 2.1 Synthesis of Graphite Ribbons.......................................................................... 20 2.2 Synthesis of Polyphenylene Ribbons................................................................ 22 2.3 Synthesis of Ladder Polymers .......................................................................... 29 2.4 Transmission Electron Microscopy of Ribbons................................................ 32 2.5 Cyclodehydrogenation of Ribbons ................................................................... 34 2.6 UV/Vis-Spectroscopy of Graphite Molecules .................................................. 39 2.7 Summary........................................................................................................... 43 2.8 References......................................................................................................... 44 3 FROM PYRENE TO POLYCYCLIC AROMATIC HYDROCARBONS CONTAINING NITROGEN..................................................................................................................... 48 3.1 Clar rule and Peripheries................................................................................... 48 3.2 Synthesis of the Building Block 3-13 ............................................................... 50 3.3 Synthesis of Extended PAHs ............................................................................ 55 3.4 Spectroscopic and Electrochemical Properties ................................................. 59 3.5 Reductive protonation and alkylation of 3-20 .................................................. 67 3.5.1 Reduction of 3-20 by using Co(Cp)2 ........................................................ 69 3.5.2 Reduction of 3-20 by using SnCl2 ............................................................ 69 3.5.3 Reduction of 3-20 by using PhLi.............................................................. 71 3.6 Summary........................................................................................................... 72 3.7 References......................................................................................................... 73 4 FROM PYRENE TO THE LARGEST PHTHALOCYANINES................................... 79 4.1 Synthesis and physical properties of phthalocyanines...................................... 79 4.1.1 Synthesis ................................................................................................... 80 4.1.2 Synthesis of metal-ion-containing Pcs (MPc)........................................... 81 4.1.3 The crystal structure of phthalocyanines .................................................. 82 4.1.4 Spectroscopic properties ........................................................................... 83 4.1.5 Discotic and columnar mesophases of Pcs ............................................... 84 4.1.6 Conductivity of Pcs................................................................................... 84 4.2 Synthesis of extended Pcs................................................................................. 86 4.3 Characterization of extended Pc ....................................................................... 90 4.4 Introduction of n-dodecyl chains ...................................................................... 92 4.4.1 Synthesis ................................................................................................... 92 4.4.2 Characterization of second extended Pc ................................................. 101 4.4.3 DSC and TGA......................................................................................... 102 4.4.4 2D-WAXS............................................................................................... 103 4.5 Summary......................................................................................................... 104 4.6 References....................................................................................................... 104 5 FROM PYRENE TOWARDS PHENANTHROLINE LIGANDS FOR METAL COMPLEXATION................................................................................................................................... 109 5.1 Ruthenium (II) Complexes ............................................................................. 109 5.2 Synthesis of Phenanthroline Ligands.............................................................. 114 5.3 Synthesis of Ru-complexes using ligands 5-17 and 5-18 ............................... 121 5.4 Synthesis of a Copper (II) complex ................................................................ 124 5.5 Synthesis of a Pt(II)-complex ......................................................................... 125 5.6 Spectroscopic properties ................................................................................. 127 5.7 Summary......................................................................................................... 131 5.8 References....................................................................................................... 132 6 CONCLUSIONS AND OUTLOOK................................................................................ 137 7 EXPERIMENTAL SECTION......................................................................................... 142 7.1 General Methods............................................................................................. 142 7.2 Synthesis ......................................................................................................... 143 7.2.1 2,7-Di-tert-butylpyrene-4,5,9,10-tetraone (1-32) ................................... 143 7.2.2 2,7-Di-tert-butyl-4,5:9,10-bis(2,5-di-p-dodecyl-phenylcyclopenta)- [e,l]pyrene-5,11-dione (2-7)...................................................................................
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