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Metal-Catalyzed and Aryne-Mediated Multicomponent Approaches to Heterocycles Nataliya Alexandrovna Markina Iowa State University

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Metal-Catalyzed and Aryne-Mediated Multicomponent Approaches to Heterocycles Nataliya Alexandrovna Markina Iowa State University Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2012 Metal-catalyzed and aryne-mediated multicomponent approaches to heterocycles Nataliya Alexandrovna Markina Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Organic Chemistry Commons Recommended Citation Markina, Nataliya Alexandrovna, "Metal-catalyzed and aryne-mediated multicomponent approaches to heterocycles" (2012). Graduate Theses and Dissertations. 12655. https://lib.dr.iastate.edu/etd/12655 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Metal-catalyzed and aryne-mediated multicomponent approaches to heterocycles by Nataliya Alexandrovna Markina A dissertation submitted to the graduate faculty in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Major: Organic Chemistry Program of Study Committee: Richard C. Larock, co-Major Professor Thomas J. Greenbowe, co-Major Professor Malika Jeffries-EL Yan Zhao George A. Kraus Iowa State University Ames, Iowa 2012 Copyright © Nataliya Alexandrovna Markina, 2012. All rights reserved. ii To my husband and my friend, Anton iii TABLE OF CONTENTS LIST OF ABBREVIATIONS .................................................................................................x CHAPTER 1. Dissertation organization ...............................................................................1 CHAPTER 2. Multicomponent Approaches to the Synthesis of 5-Membered Fused Aromatic Heterocycles. A Review. 2.1. INTRODUCTION ..............................................................................................................6 2.2. MCPs IN THE SYNTHESIS OF INDOLES ......................................................................7 2.2.1. Modifications of the Fischer indole synthesis .....................................................8 2.2.2. Modifications of the Ugi reaction ......................................................................11 2.2.3. Pd, Cu or Pd/Cu-catalyzed MCPs for indole formation ....................................13 2.2.4. Other MCPs for the synthesis of indoles ...........................................................21 2.3. MCPs IN THE SYNTHESIS OF BENZOFURANS ........................................................23 2.3.1. MCPs for the synthesis of benzofurans from 2-halophenols .............................23 2.3.2. MCPs for the synthesis of benzofurans from phenols or 2-hydroxybenzaldehydes ...................................................................................26 2.3.3. MCPs for the synthesis of benzofuran analogues ..............................................29 2.4. MCPs IN THE SYNTHESIS OF BENZOTHIOPHENES ...............................................30 2.5 MCPs IN THE SYNTHESIS OF INDAZOLES ...............................................................31 2.6. MCPs IN THE SYNTHESIS OF INDOLIZINES, PYRYDOINDOLES, PYRIDOISOINDOLES ....................................................................................................32 iv 2.7. MCPs IN THE SYNTHESIS OF BENZIMIDAZOLES ..................................................34 2.8. MCPs IN THE SYNTHESIS OF BENZOXAZOLES AND BENZISOXAZOLES .......38 2.9. MCPs IN THE SYNTHESIS OF BENZOTHIAZOLES .................................................39 2.10. CONCLUSIONS ............................................................................................................40 2.11. REFERENCES ...............................................................................................................40 CHAPTER 3. Solution-Phase Parallel Synthesis of a Diverse Library of 1,2-Dihydroisoquinolines. 3.1. ABSTRACT .....................................................................................................................48 3.2. INTRODUCTION ............................................................................................................49 3.3. RESULTS AND DISCUSSION 3.3.1. Library construction ...........................................................................................50 3.3.2. Preparation of building blocks ...........................................................................52 3.3.3. Diversification ....................................................................................................58 3.4. CONCLUSIONS ..................................................................................................62 3.5. ACKNOWLEDGEMENT ....................................................................................63 3.6. EXPERIMENTAL 3.6.1. General remarks .................................................................................................63 3.6.2. General procedure for preparation of the 2-(1-alkynyl)benzaldehydes .............64 3.6.3. General procedure for preparation of the 1,2-dihydroisoquinolines ..................72 3.6.4. Data for the 1,2-dihydroisoquinolines subjected to further elaboration ............73 3.6.5. Data for selected 1,2-dihydroisoquinolines .......................................................81 v 3.6.6. General procedure for preparation of the 1-(3-indolyl)-1,2-dihydroisoquinolines ............................................................ 82 3.6.7. Data for 1-(3-indolyl)-1,2-dihydroisoquinolines subjected to further elaboration ............................................................................................. 83 3.6.8. Data for selected 1-(3-indolyl)-1,2-dihydroisoquinolines ............................... 85 3.6.9. General procedure for the microwave-assisted Sonogashira coupling ............ 87 3.6.10. Data for selected 1,2-dihydroisoquinolines prepared via Sonogashira coupling ........................................................................................ 88 3.6.11. General procedure for the microwave-assisted Suzuki-Miyaura coupling .......................................................................................................... 90 3.6.12. Data for selected 1,2-dihydroisoquinolines prepared via Suzuki-Miyaura coupling ............................................................................... 91 3.7. REFERENCES ............................................................................................................... 97 CHAPTER 4. Efficient Microwave-assisted One-pot Three-component Synthesis of Indoles under Sonogashira Conditions. 4.1. ABSTRACT .................................................................................................................. 100 4.2. INTRODUCTION ........................................................................................................ 100 4.3. RESULTS AND DISCUSSION ................................................................................... 102 4.4. CONCLUSIONS .......................................................................................................... 109 4.5. ACKNOWLEDGEMENT ............................................................................................ 110 4.6. EXPERIMENTAL vi 4.6.1. General remarks ............................................................................................ 110 4.6.2. General procedure for preparation of the N,N-dimethyl-2-iodoanilines ....... 111 4.6.3. Preparation of methyl 4-dimethylamino-3-iodobenzoate ............................. 112 4.6.4. General procedure for preparation of the N-trifluoroacetyl-2-iodoanilines .................................................................. 112 4.6.5. General procedure for the microwave-assisted, one-pot synthesis of 1-methylindoles ....................................................................................... 114 4.6.6. General procedure for the microwave-assisted, one-pot synthesis of 1H-indoles ................................................................................................... 117 4.7. REFERENCES ............................................................................................................. 120 CHAPTER 5. Efficient Microwave-assisted One-pot Three-component Synthesis of 2,3-Disubstituted Benzofurans under Sonogashira Conditions. Approaches Towards Total Syntheses Amurensin H, Gnetuhainin B, and Gnetuhainin F. 5.1. ABSTRACT .................................................................................................................. 123 5.2. INTRODUCTION ........................................................................................................ 123 5.3. RESULTS AND DISCUSSION 5.3.1. Optimization of the reaction conditions ......................................................... 127 5.3.2. Evaluation of the reaction scope and limitations ........................................... 130 5.3.3. Study of the additional processes and further diversification ........................ 139 5.3.4. Approaches towards total syntheses of Amurensin H, Gnetuhainin B, vii and Gnetuhainin F ......................................................................................... 141 5.4. CONCLUSIONS .......................................................................................................... 151 5.5. ACKNOWLEDGEMENT ............................................................................................ 151 5.6. EXPERIMENTAL 5.6.1. General
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