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Rylene Bisimide-Diarylethene Photochromic Systems for Non-Destructive Memory Read-Out

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Rylene Bisimide-Diarylethene Photochromic Systems for Non-Destructive Memory Read-Out Rylene Bisimide-Diarylethene Photochromic Systems for Non-destructive Memory Read-out Dissertation zur Erlangung des naturwissenschaftlichen Doktorgrades der Julius-Maximilians-Universität Würzburg vorgelegt von Martin Berberich aus Amorbach Würzburg 2012 2 Eingereicht bei der Fakultät für Chemie und Pharmazie am: 10.08.2012 1. Gutachter: Prof. Dr. Frank Würthner 2. Gutachter: Prof. Dr. Markus Sauer der schriftlichen Arbeit 1. Prüfer: Prof. Dr. Frank Würthner 2. Prüfer: Prof. Dr. Markus Sauer 3. Prüfer: Prof. Dr. Tobias Brixner des öffentlichen Promotionskolloquiums Tag des öffentlichen Promotionskolloquiums: 29.10.2012 Doktorurkunde ausgehändigt am: _________________________ 3 4 Wer nichts als Chemie versteht, versteht auch die nicht recht. ca. 1790 Georg Christoph Lichtenberg (1742–1799) 5 List of Abbreviations List of Abbreviations A acceptor AIBN azobisisobutyronitrile APCI atmospheric-pressure chemical ionization BOC N-tert-butoxycarbonyl c closed form of photochrome CI conical intersection CT charge transfer CV cyclic voltammetry D donor DAE diarylethene DAEC closed form of diarylethene DAEO open form of diarylethene DBN 1,5 diazabicyclo[4.3.0]non-5-ene DCC N,N’-dicyclohexylcarbodiimide DCTB 2-[(2E)-3-(4-tert-butylphenyl)-2-methylprop-2-enylidene]malononitrile diglyme 1-methoxy-2-(2-methoxyethoxy)ethane DMF N,N-dimethylformamide DMSO dimethyl sulfoxide ESI electrospray ionization FRET Förster resonance energy transfer FWHM full width half maximum HOMO highest occupied molecular orbital HRMS high resolution mass spectrometry IC internal conversion ISC intersystem crossing lit. literature LUMO lowest unoccupied molecular orbital MALDI Matrix-assisted laser desorption/ionization MCH methylcyclohexane mCPBA meta-chloroperoxybenzoic acid mp melting point MS mass spectrometry NBS N-bromosuccinimide NIR near infrared NMP N-methyl-2-pyrrolidone NMR nuclear magnetic resonance 6 List of Abbreviations o open form of photochrome OMEM organic memory ® Oxone 2KHSO5•KHSO4•K2SO4 PET photoinduced electron transfer PBI perylene bisimide PSS photostationary state RC ring closure ref. reference RO ring opening RT reaction time rt room temperature S0 singlet ground state S1 first singlet excited state SEC spectroelectrochemistry SOMO singly occupied molecular orbital T1 lowest triplet state TBAHFP tetrabutylammonium hexafluorophosphate TBI terrylene bisimide TC-SPC time-correlated single-photon counting THF tetrahydrofuran TMP 2,2,6,6-tetramethylpiperidine TOF time-of-flight UV ultraviolet vis visible VR vibrational relaxation Abbreviations for NMR characterization ap anti-parallel isomer of diarylethene brs broad singlet d doublet dd doublet of doublets m multiplet p parallel isomer of diarylethene s singlet sept septet t triplet TMS tetramethylsilane 7 Table of Contents Table of Contents 1 Introduction and Aim of the Thesis ............................................................................................... 11 2 State of Knowledge and Literature Survey .................................................................................... 16 2.1 Photochromism ...................................................................................................................... 16 2.2 Diarylethenes ......................................................................................................................... 18 2.3 Electrochromic Behavior and Redox Properties of Diarylethenes ........................................ 24 2.4 Photochromic Compounds as Prototypes for Data Storage Systems .................................... 27 2.5 Excursion: Photoinduced Energy- and Electron-Transfer Processes .................................... 33 2.6 Photochromically Controlled Switching of Fluorescence by Energy or Electron Transfer .. 40 2.7 References ............................................................................................................................. 50 3 Energy-Level Tuning of Photochromic Switches.......................................................................... 55 3.1 Variation of Electron-Acceptor Substituents ......................................................................... 55 3.2 Synthesis ................................................................................................................................ 56 3.3 Absorption Data ..................................................................................................................... 57 3.4 Cyclic Voltammetry .............................................................................................................. 60 3.5 Conclusions ........................................................................................................................... 62 3.6 Experimental Section ............................................................................................................. 63 3.6.1 Materials and Methods .................................................................................................. 63 3.6.2 Synthesis and Characterization ...................................................................................... 64 3.7 References ............................................................................................................................. 70 4 Terrylene Bisimide-Diarylethene Containing Photochromic System ........................................... 72 4.1 Introduction ........................................................................................................................... 72 4.2 Synthesis of Photochromic System and Reference Diarylethene .......................................... 73 4.3 Absorption and Emission Spectroscopy ................................................................................ 77 4.4 Cyclic Voltammetry and Driving Force Calculation ............................................................. 82 4.5 Photoswitching and Read-out Behavior ................................................................................ 85 4.6 Conclusions ........................................................................................................................... 88 4.7 Experimental Section ............................................................................................................. 89 8 Table of Contents 4.7.1 Materials and Methods ...................................................................................................89 4.7.2 Synthesis and Characterization ......................................................................................90 4.8 References ..............................................................................................................................98 5 Perylene Bisimide-Diarylethene Containing Photochromic Dyad ............................................... 100 5.1 Introduction ..........................................................................................................................100 5.2 Synthesis of Target Compound and Reference Molecules ...................................................101 5.3 Absorption and Emission Spectroscopy ...............................................................................105 5.4 Cyclic Voltammetry and Driving Force Calculation............................................................111 5.5 Photophysical Studies ..........................................................................................................114 5.6 Conclusions ..........................................................................................................................118 5.7 Experimental Section ...........................................................................................................119 5.7.1 Materials and Methods .................................................................................................119 5.7.2 Synthesis and Characterization ....................................................................................120 5.8 References ............................................................................................................................130 6 Comparison of Known and New Rylene Bisimide-Diarylethene Dyads ..................................... 133 7 Summary ...................................................................................................................................... 138 7.1 Summary in English .............................................................................................................138 7.2 Zusammenfassung (Summary in German) ...........................................................................144 Appendix .............................................................................................................................................. 150 Supplements for Chapter 4 – Two Additional Terrylene Bisimide Dyad Systems ..........................150 Synthesis ..........................................................................................................................................151 Absorption and Emission Studies ....................................................................................................152 Experimental Section .......................................................................................................................154 References ........................................................................................................................................159 List of Publications .............................................................................................................................
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