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Catalytic Methods for the Synthesis of Spirooxindoles, Pyrroloindolines, and Flavanones Anthony Gerten Iowa State University

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Catalytic Methods for the Synthesis of Spirooxindoles, Pyrroloindolines, and Flavanones Anthony Gerten Iowa State University Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2016 Catalytic methods for the synthesis of spirooxindoles, pyrroloindolines, and flavanones Anthony Gerten Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Organic Chemistry Commons Recommended Citation Gerten, Anthony, "Catalytic methods for the synthesis of spirooxindoles, pyrroloindolines, and flavanones" (2016). Graduate Theses and Dissertations. 15918. https://lib.dr.iastate.edu/etd/15918 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]. Catalytic methods for the synthesis of spirooxindoles, pyrroloindolines, and flavanones by Anthony Gerten 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: Levi Stanley, Major Professor George Kraus Art Winter Yan Zhao Javier Vela Iowa State University Ames, Iowa 2016 Copyright © Anthony Gerten, 2016. All rights reserved. ii DEDICATION This thesis is dedicated to the Blessed Virgin Mary, on whose constant intercession I rely for help with everything in life. It is also dedicated to my lovely wife Kaity, who has waited with angelic patience for my arrival at this point, and to all of my family and friends who have struggled with me through the years. iii TABLE OF CONTENTS Page DEDICATION......................................................................................................... ii GLOSSARY OF TERMS .......................................................................................... v ACKNOWLEDGMENTS ......................................................................................... vii ABSTRACT ............................................................................................................... x CHAPTER 1 ARENES AND HETEREOARENES AS 2-π-ELECTRON REACTION PARTNERS IN CATALYTIC, ASYMETTRIC, DEAROMATIVE CYCLOADDITIONS: A REVIEW ........................................................................... 1 General Introduction ............................................................................................ 1 Enantioselective dearomative cycloadditions via carbenoid species ................... 1 Enantioselective dearomative cycloadditions catalyzed by chiral Lewis acids... 15 Enantioselective dearomative cycloadditions via cascade reactions involving allylic substitution ................................................................................................ 24 Enantioselective dearomative cycloadditions catalyzed by chiral phosphoric acids............. ........................................................................................................ 26 Enantioselective dearomative cycloadditions via iminium ion catalysis ............. 28 Enantioselective dearomative cycloadditions: conclusions and outlook ............. 30 Thesis organization .............................................................................................. 31 References............................................................................................................ 32 CHAPTER 2 ENANTIOSELECTIVE, DEAROMATIVE [3+2] CYCLOADDITIONS OF INDOLES WITH AZOMETHINE YLIDES DERIVED FROM ALANINE IMINO ESTERS ......................................................................... 37 Abstract............................................................................................................... 37 Introduction ......................................................................................................... 37 Identification of reaction conditions .................................................................... 39 Scope of alanine-derived imino esters… ............................................................. 43 Additional Substrate Scope................................................................................. 45 Effects of single enantiomer dipoles on reaction outcomes ................................. 47 Conclusion........................................................................................................... 48 Experimental details............................................................................................. 49 References............................................................................................................ 71 iv CHAPTER 3 CATALYTIC, ENANTIOSELECTIVE, NITRILE IMINE CYCLOADDITIONS WITH METHYLENEINDOLINONES ................................ 74 Abstract ................................................................................................................ 74 Introduction ......................................................................................................... 74 Identification of reaction conditions .................................................................... 76 Scope of dipolarophiles........................................................................................ 78 Scope of dipoles ................................................................................................... 81 Competition reactions of dipolarophiles .............................................................. 82 Competition reactions of dipoles ......................................................................... 84 Conclusion........................................................................................................... 85 Experimental details............................................................................................. 86 References ............................................................................................................ 122 CHAPTER 4 PALLADIUM-CATALYZED CONJUGATE ADDITION OF ARYLBORONIC ACIDS TO 2-SUBSTITUTED CHROMONES IN AQUEOUS MEDIA ...................................................................................................................... 125 Abstract ................................................................................................................ 125 Introduction… ...................................................................................................... 125 Identification of reaction conditions .................................................................... 126 Scope of arylboronic acids ................................................................................... 132 Scope of enones ................................................................................................... 133 Conclusion........................................................................................................... 134 Experimental details............................................................................................. 135 References............................................................................................................ 152 CHAPTER 5 CONCLUSIONS............................................................................. 155 v GLOSSARY OF TERMS AgClO4 silver perchlorate Cu(OTf)2 copper (II) triflate DMSO dimethyl sulfoxide dr diastereomeric ratio DBU 1,8-diazabicyclo[5.4.0]undec-7-ene ee enantioenrichment ESI Electrospray Ionization GC Gas Chromatography HPLC High Performance Liquid Chromatography HRMS High Resolution Mass Spectrometry IR Infrared Mg(NTf)2 magnesium Triflimide MHz Megahertz M Molar MS Molecular Sieves NaTFA Sodium Trifluoroacetate NEt3 Triethylamine NMR Nuclear Magnetic Resonance Pd(TFA)2 Palladium (II) trifluoroacetate QTOF Quadrupole Time of Flight THF Tetrahydrofuran TLC Thin Layer Chromatography vi tR retention time UV Ultraviolet vii ACKNOWLEDGMENTS I have a lot of individuals to whom I owe a debt of gratitude for my growth and development during my graduate school years. First and foremost, I am thankful to God whose gracious providence and guiding hand throughout my entire life have brought me to this point. I am also thankful for my lovely wife Kaity who has shown inexhaustible love, support, and patience throughout the ups and downs of graduate student life. I’m excited to find out what our future holds. To my parents, Margaret and Lewis Gerten, thank you for all of the sacrifices you have made for me throughout my life to help me stay on the straight and narrow. I also need to express gratitude to my siblings, William, Robert, and Yvonne, and to our close family friend, Benjamin Vick, for all of their love, support, and kindness throughout the years. To my advisor, Dr. Levi Stanley, thank you for teaching me so much over these last five years. You work very hard to make sure that your students have everything they need to succeed. I know I’ve made a number of mistakes that have caused headaches for you, and I appreciate your patience. I don’t know how this happens, but for every solution you propose that would work for anyone else I seem to find a way to inadvertently create a problem. I am also thankful to my lab mates. I appreciate your understanding of the fact that seven days without a pun makes one week (weak). Thank you for listening to all of them my puns. I understand that a glossary of terms is optional under ISU dissertation standards, but I included a glossary of terms for you to gloss over. I’m glad you
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