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Application of Novel Phosphine Ligands in Palladium-Catalyzed Cross-Coupling Reactions

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Application of Novel Phosphine Ligands in Palladium-Catalyzed Cross-Coupling Reactions Leibniz-Institut für Katalyse e.V. an der Universität Rostock Application of Novel Phosphine Ligands in Palladium-Catalyzed Cross-Coupling Reactions Dissertation zur Erlangung des akademischen Grades doctor rerum naturalium (Dr. rer. nat.) der Mathematisch-Naturwissenschaftlichen Fakultät der Universität Rostock vorgelegt von Christian Torborg, geb am. 8.3.1980 in Stade Rostock, 3. April 2009 urn:nbn:de:gbv:28-diss2009-0174-3 ii Die vorliegende Arbeit entstand in der Zeit von April 2006 bis März 2009 am Leibniz- Institut für Katalyse e.V. an der Universität Rostock. Gutachter der Dissertation 1. Prof. Dr. Matthias Beller, Universität Rostock 2. Prof. Dr. Carsten Bolm, RWTH Aachen Termin der Rigorosumsprüfung: 11.6.2009 1. Prüfer: Prof. Dr. Matthias Beller (Hauptfach: Organische Chemie) 2. Prüfer: Prof. Dr. Friedemann W. Nerdinger (Nebenfach: Arbeits- und Organisationspsychologie) Termin der öffentlichen Verteidigung: 18.6.2009 iii Weil du nur einmal lebst willst du dass sich was bewegt bevor du gehst Du schreibst Geschichte an jedem Tag denn jetzt und hier bist du ein Teil von ihr Madsen, Du schreibst Geschichte iv Danksagung Mein besonderer Dank gebührt meinem Mentor Herrn Prof. Dr. Matthias Beller für die Aufnahme in die Arbeitsgruppe, die anregenden und motivierenden Diskussionen und den hervorragend ausgestatteten Arbeitsplatz. Darüberhinaus möchte ich meinen Themenleitern Dr. Alexander Zapf und Dr. Helfried Neumann für die unkomplizierte und freundliche Zusammenarbeit sowie die hilfreichen Disskussionen danken. Danken möchte ich vor allem auch meiner Arbeitsgruppe für die gute Zusammenarbeit: Dr. Anne Brennführer, Sandra Leiminger, Thomas ‚Schulle’ Schulz, Andreas ‚Dandy’ Dumrath, Dr. Alexey Sergeev, Dr. Pazhmalai Anbarasan und Dr. Thomas Schareina. Für ihre Geduld und die gute Arbeitsatmosphäre im Labor bin ich außerdem Dr. Irina Jovel, Saisuree Prateeptongkum, Dr. Kristin Mertins, Dr. Jette Kischel und Dr. Jun Huang zu Dank verpflichtet. Allen Freunden und Kollegen am Leibniz-Institut für Katalyse e.V. danke ich für drei produktive und fröhliche Jahre, allen voran Dr. Benjamin Schäffner, Björn ‚Hardy’ Loges, Dr. Hanns-Martin Kaiser, Dr. Bianca Bitterlich, Kristin Schröder, Dr. Stephan ‚Sentha’ Enthaler, Dr. Angelika ‚Angie’ Preetz, Christian Fischer, Dr. Marko Hapke, Irene Piras, Daniele Addis, Dr. Karolin Alex, Dr. Marina Gruit, Dr. Thomas ‚Bob’ Schmidt, Henry Postleb, Markus Klahn, Dr. Torsten ‚Brewery’ Beweries, Dr. Anne Grotevendt, Dr. Gnuni Karapetyan, Sebastian ‚Simmi’ Imm, Albert ‚Peter’ Boddien, Stephan Peitz, Sebastian Bähn, Lorenz ‚Lolli’ Neubert, Felix Gärtner, Gerrit Wienhöfer, Christoph Stelt, Fabian Fischer, Nico Weding, Stefan Schulz, Dr. Giulia Erre, Dr. Bernhard Hagemann, Dr. Dimitry Redkin, Dr. Björn Spillker, Dr. Stefan Klaus, Dr. Jens Holz, Dr. Annegret Tillack, Dr. Ralf Jackstell, Dr. Man-Kin Tse, Dr. Haijun Jiao, Dr. Kathrin Junge, Dr. Hendrik Junge, und vielen mehr. v Den Mitgliedern des JCFs Rostock möchte ich für die gute Zeit bei den gemeinschaftlich organisierten Veranstaltungen danken, namentlich Arne Bernsdorf, Anke Flemming, Dr. Jennifer Hefner, Katja Neubauer und Dr. Jan von Langermann. Weiterhin danke ich der freitagabendlichen Diskussionsrunde für den wissenschaftlichen und kulturellen Austausch. Der analytischen Abteilung gebührt ebenfalls mein Dank: Dr. Christine Fischer, Dr. Anke Spannenberg, Susanne Buchholz, Susann Schareina, Anja Kammer, Sigrun Rossmeisel, Kathleen Mevius, Dr. Wolfgang Baumann, Andreas Koch und Dr. Dirk Michalik. Dr. Thomas Dwars vom Einkauf danke ich für die unkomplizierte und effiziente Zusammenarbeit, sowie dem Glasbläser Matthias Auer für das Anfertigen mancher Spezialapparatur. Meinen Eltern, meinen Freunden und meiner Schwester Claudia danke ich besonders herzlich für den Rückhalt. Nicht zuletzt möchte ich mich bei meinen ehemaligen Mitbewohnern Falko Bergelt, Daniel Nowatschin, Franziska Seidel, Lea Maciolek, Benjamin Rudel, Roswitha Nast und Jan Flessel die ihre Unterstützung und die fröhliche Zeit in Rostock bedanken. vi Abstract This thesis describes the application of 2-phosphino-N-arylindoles, -pyrroles and -imidazoles as ligands in Pd-catalyzed C–C, C–N and C–O bond forming reactions. Based on prior studies, 2-phosphino-N-arylindoles and -pyrrols were found to form efficient catalysts with Pd-salts in the Sonogashira-Hagihara coupling of (hetero)aryl bromides and the Pd-catalyzed monoarylation of ammonia. The novel imidazole-based phosphines were prepared after a straightforward modular synthesis and are notably stable towards air. They were successfully employed in the Pd-catalyzed phenol synthesis, the Heck-Cassar coupling of aryl chlorides, and the Pd-catalyzed monoarylation of ammonia. Furthermore, mechanistic studies in the Pd-catalyzed hydroxylation were undertaken. In der vorliegenden Dissertation wird die Anwendung von Dialkyl-heteroarylphosphinen als Liganden in palladiumkatalysierten Bindungsknüpfungen beschrieben. Die zuvor beschriebenen Indol- und Pyrrol-basierten Phosphine wurden erfolgreich in der Sonogashira-Hagihara-Kupplung von Aryl- und Heteroarylbromiden und der palladiumkatalysierten selektiven Anilinsynthese eingesetzt. Die Imidazolderivate hingegen stellen eine neuartige Ligandenklasse für Kreuzkupplungen dar. Sie konnten mit einer modularen Synthesemethode bequem dargestellt werden und sind äußerst luftstabil. Mit auf ihnen basierenden Palladium-Katalysatoren konnten Arylchloride effizient kupferfrei mit Alkinen umgesetzt, sowie Phenole wie auch Aniline aus Arylhaliden synthetisiert werden. Des weiterten wurden mechanistische Untersuchungen in der palladiumkatalysierten Phenolsynthese durchgeführt. vii Table of Contents 1 Introduction ............................................................................... 1 1.1 Catalysis................................................................................................................ 1 1.2 Homogeneous Catalysis ....................................................................................... 4 1.3 The Role of Palladium in Homogeneous Catalysis ............................................... 6 1.4 Industrial Applications of Pd-catalyzed C–C and C–N Bond Formations............ 11 1.4.1 Heck-Mizoroki Reactions...................................................................................................13 1.4.2 Suzuki-Miyaura Reactions.................................................................................................17 1.4.3 Sonogashira-Hagihara Reactions .....................................................................................23 1.4.4 Carbonylations...................................................................................................................24 1.4.5 Cyanations.........................................................................................................................25 1.4.6 Other Pd-Catalyzed C–C Coupling Reactions ..................................................................26 1.4.7 Buchwald-Hartwig Aminations...........................................................................................28 1.4.8 Miscellaneous....................................................................................................................30 1.4.9 Conclusions and Outlook...................................................................................................30 1.5 Sonogashira-Hagihara Reaction and Heck-Cassar Coupling ............................. 31 1.5.1 Basic Principles .................................................................................................................31 1.5.2 Catalysts and Reaction Conditions ...................................................................................33 1.5.3 Catalysts Bearing Monodentate Alkyl-Substituted Phosphines ........................................34 1.6 Palladium-Catalyzed Coupling of Ammonia and Hydroxide with Aryl Halides .... 41 2 References.............................................................................. 47 3 Objectives of this Work ........................................................... 59 4 Publications............................................................................. 61 4.1 Palladium Catalysts for Highly Selective Sonogashira Reactions of Aryl and Heteroaryl Bromides............................................................................................ 61 4.2 Practical Imidazole-Based Phosphine Ligands for the Selective Palladium- Catalyzed Hydroxylation of Aryl Halides ............................................................. 68 4.3 Palladium-Catalyzed Hydroxylations of Aryl Halides under Ambient Conditions 73 4.4 Improved Palladium-Catalyzed Sonogashira Reactions of Aryl Chlorides.......... 79 4.5 A General Palladium-Catalyzed Amination of Aryl Halides with Ammonia ......... 88 viii List of Abbreviations a year Ac acetyl Ad adamantyl API active pharmaceutical ingredient Ar aryl AT2 angiotensin II BBN 9-borabicyclo[3.3.1]nonane BINAP 2,2’-bis(diphenylphosphino)-1,1’-binaphtyl Bn benzyl BOC di-tert-butyl dicarbonate Bu butyl CataCXium® A di-1-adamantyl-n-butylphosphine CataCXium® PIntB 2-(di-tert-butylphosphino)-N-phenylindole CataCXium® PtB 2-(di-tert-butylphosphino)-N-phenylpyrrole CETP cholesteryl ester transfer protein CP ceruloplasmin COD cyclooctadieenyl COX-2 prostaglandin-endoperoxide synthase 2 CNS central nervous system Cy cyclohexyl D-A Diels-Alder dba trans, trans-dibenzylideneacetone DABCO 1,4-diazabicyclo[2.2.2]octane DE dissociation energy DFT density functional
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