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Design and Synthesis of Pentacene Derivatives Design Und Synthese Design and synthesis of pentacene derivatives Design und Synthese von Pentacenderivaten Der Naturwissenschaftlichen Fakultät der Friedrich-Alexander-Universität Erlangen-Nürnberg zur Erlangung des Doktorgrades Dr. rer. nat. vorgelegt von Andreas R. Waterloo aus Eschenbach i. d. Opf. Als Dissertation genehmigt von der Naturwissenschaftlichen Fakultät der Friedrich- Alexander Universität Erlangen-Nürnberg Tag der mündlichen Prüfung: 26.11.2014 Vorsitzender des Promotionsorgans: Prof. Dr. Jörn Wilms Gutachter/in: Prof. Rik R. Tykwinski PhD Prof. Dr. Nicolai Burzlaff Die vorliegende Arbeit wurde am Institut für Organische Chemie der Friedrich- Alexander-Universität Erlangen-Nürnberg in der Zeit von Juni 2010 bis September 2014 unter Anleitung von Prof. Rik R. Tykwinski PhD angefertigt. For my family, my friends, and for Simone “Learn the rules like a pro, so you can break them like an artist.“ – Pablo Picasso Acknowledgments First of all I want to thank my supervisor Prof. Rik R. Tykwinski for giving me the chance to carry out research in his laboratories. He has put enormous efforts in my education and helped me to understand at least some parts of the world of organic chemistry. He has made a synthetic organic chemist out of me. Working in his group has also the great side effect of reinventing own English skills. Thanks also to Dr. Milan Kivala who helped with chemical problems at any time. The Graduate School of Molecular Science (GSMS) and the Georg-Kurlbaum- Stiftung are gratefully acknowledged for financial support. Thanks to Prof. Oana Jurchescu at Wake Forest University (Winston-Salem, United States), to Sebastian Etschel, and the Halik group at FAU for performing the transistor devices. Thanks to Frank Strinitz (Burzlaff group) at FAU for the collaboration and the interest in our precursor materials. Thanks to Dr. Rubén D. Costa and Ruben Casillas (Guldi group) at FAU for performing the singlet fission topic. I want to thank the whole Tykwinski group as well as the Kivala group for the very nice group atmosphere, especially, Dominik Prenzel, Maximilian Krempe, Vincent Oerthel, Johanna Januszewski, Stephanie Frankenberger, Michael Franz, Dominik Wendinger, Vroni Walter, Katrin Schmidt, Sebastian Etschel, Matthias Schulze, Julia Tyrach, Fabian Fritze, Bettina Gliemann, Theresa Mekelburg, Michael Grunst, Tobias Schaub, and Ute Meinhardt for some unforgettable times during my PhD studies, most of them in our “Souschl Room”. Special thanks go to Dr. Adrian Murray. During his stay in Erlangen we have become good friends. Thank you to Dr. Eike Jahnke for the help at the very beginning of my career. Thank you to Matthias Adam (Maze) for the discussions about computer problems. Special thanks go to the X-ray crystallographic staff members, Dr. Frank Hampel and Wolfgang Donaubauer, for the large number of solved structures. Thank you to the service staff members: Christian Placht (NMR), Dr. Harald Maid (NMR), Prof. Dr. Walter Bauer (NMR), Margarte Dzialach (MS analysis), Wolfgang Donaubauer (MS analysis), Eva Zeisel (microanalysis), Holger Wolfarth (electricity facility), Horst Meier (mechanics facility), Stefan Fronius (glas blower facility), Bahram Saberi (glas blower facility), and Pamela Hampel (group secretary). Thank you very much Simone Berngruber. You are simply great! Special thanks to Dr. Wolfgang Brenner. We have tried to revolutionize the GSMS Winterschool in Kirchberg. Thanks to Thomas Nasser, Thomas Dotzauer, Sebastian Lohner, Dominik Brütting, and Johannes Bayerl for being the closest friends I have. Thanks to Arno Lücken, with whom I have betted that he will make it into this thesis. Last but not least, I say thank you very much to my parents and my whole family. Without your endless support and understatement this thesis would not have been possible. Curriculum vitae Personal data Name: Andreas Reinhard Waterloo Date of birth: 20.02.1983 Born in: Eschenbach i.d. Opf. Academic career June 2010 - present PhD program in the group of Prof. Rik R. Tykwinski at the Institut für Organische Chemie at FAU Erlangen Thesis title: “Design and synthesis of pentacene derivatives” August 2009 - May 2010 Diploma thesis in the group of Prof. Rik R. Tykwinski at the Insitut für Organische Chemie at FAU Erlangen Thesis title: “Unsymmetrically substituted pentacenes” October 2003 - July 2009 Academic studies of chemistry at FAU Erlangen Military service July 2002 - May 2003 Obligatory military service at the german army (Bundeswehr) in Oberviechtach, Bavaria School education September 1993 - June 2002 Gymnasium Eschenbach i. d. Opf. (Abitur) September 1989 - 1993 Primary school, Eschenbach i . d. Opf List of publications [1] “Acenes with a Click” Waterloo, A. R.; Kunakom, S.; Hampel, F.; Tykwinski, R. R. Macromol. Chem. Phys. 2012, 213, 1020–1032. [2] “Isomerically Pure syn-Anthradithiophenes: Synthesis, Properties, and FET Performance” Lenherr, D.; Waterloo, A. R.; Goetz, K. P.; Payne, M. M.; Hampel, F.; Jurchescu, O. D.; Anthony, J. E.; Tykwinski, R. R. Org. Lett. 2012, 14, 3660–3663. [3] “An unsymmetrical pentacene derivative with ambipolar behavior in organic thin-film transistors” Etschel, S.; Waterloo, A. R.; Markgraf, J. T.; Amin, A. Y.; Hampel, F.; Jäger, C. M.; Clark, T.; Halik, M.; Tykwinski, R. R. Chem. Commun. 2013, 49, 67256727. [4] “Allenylidene Complexes Based on Pentacenequinone” Strinitz, F.; Waterloo, A. R.; Tucher, J.; Hübner, E.; Tykwinski, R. R.; Burzlaff, N. Eur. J. Inorg. Chem. 2013, 51815186. [5] “Aryl Substitution of Pentacenes” Waterloo, A. R.; Sale, A.-C.; Lehnherr, D.; Hampel, F.; Tykwinski, R. R. Beilstein J. Org. Chem. 2014, 10, 16921705. [6] “Carbon-Rich Ruthenium Allenyliden Complexes Bearing Heteroscorpionate Ligands” Strinitz, F.; Tucher, J.; Januszewski, J. A.; Waterloo, A. R.; Stegner, P.; Förtsch, S.; Hübner, E.; Tykwinski, R. R.; Burzlaff, N. Organometallics, 2014, DOI: 10.1021/om5002777. Poster presentations [1] Waterloo, A. R.; Hampel, F.; Tykwinski, R. R. “Pentacenechinocumulenes: New Semiconductors?” Gordon Research Conference on Physical Organic Chemistry, June 2013, Holderness School, USA. [2] Waterloo, A. R.; Lehnherr, D.; Hampel, F.; Goetz, K. P.; Payne, M. M.; Jurchescu, O. D.; Anthony, J. E. Tykwinski, R. R. “Isomerically Pure syn- Anthradithiophenes” ORGCHEM 2012, September 2012, Weimar, Germany. [3] Waterloo, A. R.; Kunakom, S.; Hampel F.; Tykwinski R. R. “Pentacene Chromophores via Click Chemistry.” International Symposium of Novel Aromatic Compounds (ISNA 14), July 2011, Eugene (Oregon), USA. [4] Tykwinski, R. R.; Waterloo, A. R.; Konishi, A.; Lehnherr, D.; Hampel, F. “Tautomerization in 6,13-Derivatives of Pentacene.” International Symposium of Novel Aromatic Compounds (ISNA 14), July 2011, Eugene (Oregon), USA. [5] Waterloo, A. R.; Hampel, F.; Tykwinski, R. R. “Functionalization of Pentacene.” European Association of Chemical and Molecular Science (EuChems 3), August 2010, Nürnberg, Germany. [6] Waterloo, A. R.; Hampel, F.; Tykwinski, R. R. “Pentacenes and Click- Chemistry.” Funmols workshop, April 2010, Muggendorf, Germany. Summary The scope of this research work was the synthesis and characterization of pentacene derivatives and pentacene-related materials. The most important characterization method for the products formed in the present work has been X-ray crystallographic analysis. On the basis of this work, pentacene derivatives can be classified by generally observed solid-state arrangements, of which some are beneficial for the use in optoelectronic devices. The solid-state motifs are closely related to the substitution pattern of pentacene derivatives. The present work discusses the influence of different substituents on the solid-state arrangement of pentacenes. The X-ray crystallographic theme is applied to the characterization of isomerically pure syn-anthradithiophenes, as analogs to pentacenes, and the characterization of 6,13- pentacenequinone-based materials. An attempt is made to draw correlations between solid-state structures of the detailed compounds and their properties, although this evaluation is extremely complex. Chapter 1 of this thesis gives a short introduction into the chemistry of pentacene and the distinct features of pentacene derivatives evaluated by X-ray crystallography. The introduction summarizes the current state of the field, also bridging to material science, and gives examples of previously synthesized pentacenes. Chapter 2 discusses the synthesis of unsymmetrically substituted pentacene derivatives in 6- and 13-positions. The functional groups appended to the pentacene framework include 1,2,3-triazolyl-, aryl-, and alkyl moieties. The synthesized 1,2,3- triazolyl-pyridyl-substituted pentacene derivatives can be used to investigate pentacene-porphyrin assemblies. The applied groups at the 6-and 13-postions have little effect on electronic properties of the pentacene derivatives, which is verified by UV-vis spectroscopy, emission spectroscopy, and electrochemical measurements. Nevertheless, functionalization by anthracenyl groups affords pentacene derivatives that show interesting solid-state packing and several packing motifs are compared. The reactivity of a methyl-substituted pentacene derivative is briefly discussed. The chapter closes with the synthesis and characterization of a monosubstituted pentacene derivative. Chapter 3 discusses the successful synthesis of isomerically pure syn- anthradithiophenes. A detailed study comparing syn-isomers and isomerically mixed anthradithiophenes has been conducted by UV-vis spectroscopy, emission
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