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N-Heterocyclic Silylenes As Tools in Coordination Chemistry and Catalysis

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N-Heterocyclic Silylenes As Tools in Coordination Chemistry and Catalysis N-Heterocyclic Silylenes as Tools in Coordination Chemistry and Catalysis vorgelegt von M. Sc. Chemie Yu-Peng Zhou aus Yunnan (V. R. China) Von der Fakultät II – Mathematik und Naturwissenschaften der Technischen Universität Berlin Institut für Chemie zur Erlangung des akademischen Grades Doktor der Naturwissenschaften - Dr. rer. nat. - genehmigte Dissertation Promotionsausschuss: Vorsitzender: Prof. Dr. Reinhard Schomäcker (Technische Universität Berlin) 1. Gutachter: Prof. Dr. Matthias Driess (Technische Universität Berlin) 2. Gutachter: Prof. Dr. Christian Müller (Freie Universität Berlin) Tag der wissenschaftlichen Aussprache: 13.06.2018 Berlin 2018 DISSERTATION by M. Sc. Chemistry Yu-Peng Zhou from Yunnan (P. R. China) Die vorliegende Arbeit entstand in der Zeit von Sep. 2014 bis Feb. 2018 unter der Betreuung von Prof. Dr. Matthias Driess am Institut für Chemie der Technischen Universität Berlin. Von Herzen kommend gilt mein Dank meinem verehrten Lehrer Herrn Professor Dr. Matthias Driess für die Aufnahme in seinen Arbeitskreis, für seine engagierte Unterstützung, und für die Forschungsfreiheit. Acknowledgment I would like to express my sincere gratitude to Prof. Dr. Matthias Driess for his continuous guidance, encouragement and granting academic freedom throughout my doctoral work. I sincerely thank Dr. Shenglai Yao, Dr. Gengwen Tan, Dr. Daniel Gallego, and Dr. Zhenbo Mo for their helpful scientific guidance, suggestions, and discussion. In addition, I am grateful to Dr. Yun Xiong, Dr. Chakadola Panda, Dr. Prashanth W. Menezes, Dr. Nils Lindenmaier, Dr. Xiaohui Deng, Ms. Yuwen Wang, Ms. Min Ha Kim, Mr. Maecel-Philip Luecke, Mr. Huan Wang, and all BIG-NSE graduate school friends for their help during my stay in Germany and friendship. Also, I am indebted to all the group members of the Driess group for their help and cooperation during the daily work. Acknowledgements are also given to Dr. Jean-Philippe Lonjaret for creating the nice environment of the graduate school BIG-NSE. Furthermore, I want to express my thanks to Prof. Dr. Yitzhak Apeloig (Israel Institute of Technology), Dr. Arseni Kostenko, Dr. Miriam Karni (Israel Institute of Technology) and Dr. Tibor Szilvási (University of Wisconsin-Madison) for their cooperation in theoretical calculations, Dr. Saeed Raoufmoghaddam for catalyst testing, Ms. Paula Nixdorf for single-crystal X-ray diffraction measurements, Dr. Somenath Garai for his help on structural refinements, Mr. Marc Griffel for mass measurements, and Ms. Juana Krone for CHN measurements. Moreover, Mr. Stefan Schutte, Ms. Mandy Prillwitz, and Ms. Andrea Rahmel are thanked for their daily contribution to the group. I heartfully thank my family for years of support and encouragement. I am grateful to the Cluster of Excellence UniCat for financial support and a Ph.D. fellowship from the Berlin International Graduate School of Natural Sciences and Engineering (BIG-NSE). Publications during doctoral study 1. Y. P. Zhou, S. Raoufmoghaddam, T. Szilvási, M. Driess*, Angew. Chem. Int. Ed. 2016, 55, 12868-12872. A Bis(silylene) Substituted ortho-Carborane as a Superior Ligand in the Nickel-Catalyzed Amination of Arenes 2. Y. P. Zhou, M. Karni, S. Yao, Y. Apeloig*, M. Driess*, Angew. Chem. Int. Ed. 2016, 55, 15096-15099. (Hot Paper) A Bis(silylenyl)pyridine Zero-Valent Germanium Complex and Its Remarkable Reactivity 3. Y. P. Zhou, Z. Mo, M. P. Luecke, M. Driess*, Chem. Eur. J. 2017, DOI: 10.1002/chem.201705745. (Hot Paper & Front Cover) Stereoselective Transfer Semi-Hydrogenation of Alkynes to E-Olefins with N- Heterocyclic Silylene–Manganese Catalysts 4. S. Raoufmoghaddam, Y. P. Zhou, Y. Wang, M. Driess*, J. Organomet. Chem. 2017, 829, 2-10. N-heterocyclic silylenes as powerful steering ligands in catalysis 5. Z. Mo, T. Szilvási, Y. P. Zhou, S. Yao, M. Driess*, Angew. Chem. Int. Ed. 2017, 56, 3699 –3702. (Hot Paper) An Intramolecular Silylene Borane Capable of Facile Activation of Small Molecules, Including Metal-Free Dehydrogenation of Water 6. H. Ren, Y. P. Zhou, Y. Bai, C. Cui*, M. Driess, Chem. Eur. J. 2017, 23, 5663–5667. Cobalt-Catalyzed Regioselective Borylation of Arenes: N-Heterocyclic Silylene as Electron Donors in Metal-Mediated Activation of C-H Bonds 7. M. P. Luecke, D. Porwal, A. Kostenko, Y. P. Zhou, S. Yao, M. Keck, C. Limberg, M. Oestreich, M. Driess*, Dalton Trans., 2017, 46, 16412–16418. Bis(silylenyl)-substituted Ferrocene-stabilized 6-arene Iron(0) Complexes: Synthesis, Structure and Catalytic Application ABSTRACT Low-valent main-group chemistry, especially the chemistry of N-heterocyclic silylenes (NHSis), is one of the most attractive research topics in contemporary organometallic chemistry. In this dissertation, a series of NHSis and their derivatives were developed and used as ligands to stabilize low-valent germanium compounds as well as in transition metal-mediated homogenous catalysis. The synthesis, reactivity, and electronic structure of the first Ge0 iron carbonyl complex is described in chapter 3.1. The compound was obtained from the reaction of a pyridine-based bis-NHSi ligand stabilized chlorogermyliumylidene chloride 0 precursor with Collman’s reagent, K2Fe(CO)4. Remarkably, the reaction of the Ge iron carbonyl complex with one equivalent of GeCl2⋅(dioxane) furnished the first push–pull germylone–germylene donor–acceptor complex, through the insertion of 0 0 GeCl2 into the dative Ge →Fe bond. The synthesis and structures of the first bis-NHSi-substituted ortho-carborane [(LSi:)C]2B10H10 (L=PhC(NtBu)2) and its nickel complexes are discussed in chapter 3.2. The CO stretching vibration modes of the corresponding Ni(CO)2 complex indicate that the SiII atoms in the ligand are even stronger σ donors than the PIII atoms in phosphines and CII atoms in N-heterocyclic carbene (NHC) ligands. Moreover, the strong donor character of the ligand enables NiII complex to act as an outstanding precatalyst (0.5 mol % loading) in the catalytic aminations of arenes. In chapter 3.3, the synthesis and structures of the SiII-donor supported MnII complexes, bearing a pyridine-based bis-NHSi ligand, bidentate ferrocene-based bis- NHSi ligand, and two monodentate NHSi ligands are described, respectively. They act as active and stereoselective manganese-based precatalysts (1 mol % loading) in transfer semi-hydrogenations of alkynes to give the corresponding (E)-olefins using ammonia–borane as a convenient hydrogen source under mild reaction conditions. Finally, the synthesis and structure of cobalt silyl, silylene, and η2-(Si−H) 1 1 complexes derived from N-heterocyclicsilylcarbene L Si(H)(CH2)NHC (L = CH{C=CH2}(CMe)(NAr)2, Ar = 2,6-iPr2C6H3, NHC = 3,4,5-trimethylimidazol-2- 1 ylidene) is discussed in chapter 3.4. The complex [L Si(CH2)NHC]CoH(PMe3)2 is found to be a very active (pre)catalyst for the hydrosilylation of olefins. ZUSAMMENFASSUNG Die Chemie der niedervalenten Hauptgruppen und besonders die Chemie der N- heterocyclischen Silylene (NHSis) ist einer der attraktivsten Forschungsbereiche der modernen metallorganischen Chemie. In dieser Arbeit wurden eine Reihe von NHSis sowie ihre Derivate entwickelt und als Liganden eingesetzt, um niedervalente Spezies der Gruppe 14 zu stabilisieren und, Übergangsmetalle zu Koordinieren. Des Weiteren wurden neue katalytische Anwendungen von Übergangsmetallkomplexen in Aminierungs-, Semi-Transferhydrierungs- und Hydrosilylierungsreaktionen entwickelt. Die Synthese, Reaktionsfähigkeit und Elektronenstruktur eines Ge0-Eisen- Carbonyl-Komplexes wird in Kapitel 3.1 beschrieben. Die Verbindung entstand aus der Reaktion des auf Pyridin basierenden bis-NHSi-Liganden-stabilisierten Chlorogermyliumyliden-Chlorid-Precursors mit dem Collmans Reagenz, K2Fe(CO)4. Bemerkenswert war, dass die Reaktion des Ge0-Eisencarbonylkomplexes mit einem Äquivalent des GeCl2⋅(Dioxan) durch die Einschiebung des GeCl2 in die koordinative Ge0→Fe0-Bindung den ersten Push-Pull Germylon-Germylen Donor-Akzeptor- Komplex ergab. Die Synthese und Strukturen des ersten bis-NHSi-substituierten ortho-Carborans [(LSi:)C]2B10H10 (L=PhC(NtBu)2) und seines Nickel-Komplexes sind in Kapitel 3.2 dargelegt. Die CO-Streckschwingungsarten des korrespondierenden Ni(CO)2- Komplexes weisen darauf hin, dass die SiII-Atome im Liganden noch stärkere σ- Donoren sind als die PIII-Atome in Phosphanen und die CII-Atome in N- heterocyclischen Carben (NHC)-Liganden. Außerdem kann der NiII-Komplex durch die starken Donor-Eigenschaften des Liganden als hervorragender Präkatalysator (0,5 mol % Beladung) in der katalytischen Aminierung von Arenen fungieren. In Kapitel 3.3 werden die Synthese und Strukturen der ersten SiII-Donor- unterstützten MnII-Komplexe beschrieben, die einen Pyridin-basierten bis-NHSi- Liganden, einen zweizähnigen Ferrocen-basierten bis-NHSi-Liganden und zwei einzähnige NHSi-Liganden tragen. Sie fungieren als aktive und stereoselektive Mangan-basierte Präkatalysten (1 mol % Beladung) in Semi-Transferhydrierungen von Alkinen mit Amminboran als geeigneter Wasserstoffquelle unter milden Reaktionsbedingungen wobei die korrespondierenden (E)-Olefine entstehen. Schließlich beschreibt meine Dissertationschrift in Kapital 3.4 die Synthese und Strukturen von Cobalt-Silyl, Silylen und η2-(Si−H) Komplexen aus dem N- 1 heterocyclischem Silylcarben L Si(H)(CH2)NHC (L1 = CH{C=CH2}(CMe)(NAr)2, Ar = 2,6-iPr2C6H3, NHC = 3,4,5-trimethylimidazol-2-ylidene). Der Komplex 1 [L Si(CH2)NHC]CoH(PMe3)2 erwies sich als sehr aktiver (Prä-)Katalysator für die Hydrosilylierung von Olefinen. Contents CONTENTS 1. INTRODUCTION .........................................................................................................
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