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The Frustrated Lewis Pair Concept Applied to the Functionalization of N- Heterocycles”

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The Frustrated Lewis Pair Concept Applied to the Functionalization of N- Heterocycles” Dissertation zur Erlangung des Doktorgrades der Fakultät für Chemie und Pharmazie der Ludwig-Maximilians-Universität München The Frustrated Lewis Pair Concept Applied to the Functionalization of N-Heterocycles von Milica Jaric, geb. Gvozdenac aus München 2011 Erklärung Diese Dissertation wurde im Sinne von § 13 Abs. 3 bzw. 4 der Promotionsordnung vom 29. Januar 1998 (in der Fassung der vierten Änderungssatzung vom 26. November 2004) von Herrn Prof. Dr. Paul Knochel betreut. Ehrenwörtliche Versicherung Diese Dissertation wurde selbständig und ohne unerlaubte Hilfe bearbeitet. München, am 21. Januar 2011 …..…………………………………… Milica Jaric Dissertation eingereicht am 21.01.2011 1. Gutachter: Prof. Dr. Paul Knochel 2. Gutachter: Prof. Dr. Manfred Heuschmann Mündliche Prüfung am 24.02.2011 This work was carried out from August 2007 to January 2011 under the guidance of Prof. Dr. Paul Knochel at the Department Chemie und Pharmazie of the Ludwig-Maximilians- Universität, Munich. Firstly, I would like to express my appreciation to Prof. Dr. Paul Knochel for giving me the great opportunity to do my Ph.D. in his group and for his guidance and support in the course of my scientific research. I am also very grateful to Prof. Dr. Manfred Heuschmann for agreeing to be my “Zweitgutachter” as well as Prof. Dr. Heinz Langhals, Prof. Dr. Konstantin Karaghiosoff, Prof. Dr. Hans Rudolf Pfaendler and Prof. Dr. Rudolf Knorr for their interest shown in this manuscript by accepting to be referees. I really would like to thank Laurin Melzig, Tobias Blümke and Sebastian Bernhardt for the careful correction of this manuscript. Furthermore, I want to thank Silvia Zimdars for her great support in formatting “a lot of stuff”. I would like to thank Benjamin Haag for the successful collaboration in the field of the frustrated Lewis pairs and Andreas Unsinn for the endless discussions. I would like to thank Dr. Vladimir Malakhov and Dr. Shohei Sase for the fruitful collaboration in the field of the arylzinc chemistry and Sophia Manolikakes, as well as Dr. Coura Diène for their great support in the area of the quinine functionalization. I thank all past and present co-workers I have met in the Knochel group for their kindness and their help. Special thanks to my actual and former lab mates Tobias Blümke, Dr. Stéphanie Duez, Sophia Manolikakes, Dr. Albrecht Metzger, Nadja Barl, Dr. Murthy N. Cheemala, Dr. Yi-Hung Chen and Dr. Shohei Sase for the great time together with good music. Additional thanks go to Matthias Schade, Andreas Wagner, Klaus Groll, Thomas Kunz, Cora Dunst, Tomke Bresser, Gabriel Monzon, Tobias Thaler, Andreas Steib, Christoph Sämann, Zhihua Peng, Zhi-Liang Shen, Stephanie Seel, Dr. Xavier Mollat du Jourdin, Dr. Alexei Bredihhin and Dr. Christina Despotopoulou for being fantastic colleagues. I would also like to thank Dr. Vladimir Malakhov, Simon Matthe, Beatrix Cammelade, Renate Schröder and Yulia Tsvik for their help in organizing everyday life in the lab and in the office, as well as the analytical team of the LMU for their invaluable help. I thank Demetria Dolores Pérez Hernandéz for her contribution to this work in course of her internship in the Knochel group. Special thanks to my friends Sanela Babic, Borislava Peric, Andreas Latkovic, Danijela Maric, Ljiljana and Nadja Bojic for their backup throughout this time. I would like to thank my husband Slavko for his love and support. Very special thank to my parents and my sister for their great support, throughout my studies, my Ph.D and all the other years. I couldn´t have done this without you! Part of this Ph. D. thesis have been published: S. Sase, M. Jaric , A. Metzger, V. Malakhov, P. Knochel: “One-Pot Negishi Cross-Coupling Reactions of In Situ Generated Zinc Reagents with Aryl Chlorides, Bromides, and Triflates” J. Org. Chem. 2008 , 73 , 7380. M. Jaric , B. A. Haag, A. Unsinn, K. Karaghiosoff, P. Knochel: “Highly Selective Metalations of Pyridines and Related Heterocycles Using New Frustrated Lewis Pairs or Zn- and Mg-TMP-Bases with BF 3·OEt 2” Angew. Chem. Int. Ed. 2010 , 49 , 5451 ( hot paper ); Angew. Chem. 2010 , 122 , 5582. M. Jaric , B. A. Haag, S. M. Manolikakes, P. Knochel: “Selective and Multiple Functionalization of Complex Pyridines and Alkaloids via Mg- and Zn-Organometallic Intermediates” Org. Lett. , accepted. » Ko чини дoбр o, oд њeгa сe jo ш виш e дoбр a o чek уje. « -Ivo Andric- Nobel laureate in literature 1961 Table of Contents Abbreviations ........................................................................................................................... 1 A. Introduction......................................................................................................................... 2 1. Overview....................................................................................................................................................... 2 2. Preparation of Funtionalized Organomagnesium Reagents .................................................................... 3 2.1 Direct oxidative insertion of magnesium to organic halides ................................................................... 3 2.2 The halogen/magnesium exchange reaction............................................................................................ 4 3. Preparation of Functionalized Organozinc Reagents............................................................................... 7 3.1 Direct oxidative insertion of zinc to organic halides............................................................................... 7 4. Preparation of Functionalized Organoboron Reagents............................................................................ 9 4.1 Alkylation of organomagnesium or lithium reagents with trialkyl borate............................................... 9 4.2 Pd-catalyzed cross-coupling reaction of aryl halides with bis(pinacolato)diboron............................... 10 4.3 Hydroboration ....................................................................................................................................... 10 4.4 Borylation via C-H activation ............................................................................................................... 10 4.5 Organotrifluoroborates.......................................................................................................................... 11 5. Preparation and Application of TMP-Bases............................................................................................ 12 5.1 Introduction........................................................................................................................................... 12 5.2 Magnesium amide bases ....................................................................................................................... 13 5.3 Zinc amide bases................................................................................................................................... 14 5.4 Aluminum amide bases......................................................................................................................... 15 6. Frustrated Lewis Pairs .............................................................................................................................. 16 7. Objectives ................................................................................................................................................... 19 B. Results and Discussion...................................................................................................... 21 1. Functionalization of Pyridine and its Derivatives via Regio- and Chemoselective Metalation ........... 22 1.1 Introduction........................................................................................................................................... 22 1.2. Functionalization of pyridine and its derivatives using lithium bases.................................................. 23 1.3 Regio- and chemoselective functionalitzation of pyridine and its derivatives using TMP-derived bases in the presence of BF 3·OEt 2......................................................................................................................... 25 2. Functionalization of Quinoline (31a) and its Derivatives via Regio- and Chemoselective Metalation 29 2.1 Introduction........................................................................................................................................... 29 2.2 Regio- and chemoselective functionalitzation of quinoline ( 31a ) and its derivatives using TMP-derived bases in the presence of BF 3·OEt 2 ............................................................................................................... 30 3. Preparation of New Frustrated Lewis Pairs for the Regio- and Chemoselective Functionalization of Sensitive N-Heterocycles ............................................................................................................................... 32 4. Regio- and Chemoselective Functionalization of Alkylpyridines .......................................................... 41 4.1 Isopropylpyridine .................................................................................................................................. 41 4.2 Methylpyridine...................................................................................................................................... 42 4.3 Functionalization of 2-methylpyridine ( 56c ) in benzylic position .......................................................
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