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Osmium Catalyzed Dihydroxylation and Oxidative Cleavage of Vinyl

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Osmium Catalyzed Dihydroxylation and Oxidative Cleavage of Vinyl Purdue University Purdue e-Pubs Open Access Dissertations Theses and Dissertations Fall 2013 Osmium Catalyzed Dihydroxylation And Oxidative Cleavage Of Vinyl Sulfone And Elucidation Of The inV ylsulfone Polypropionate Methodology For The yS nthesis Of The C32 esD - Methyl C28-C34 Actin Binding Tail Of Aplyronine A Thomas Paul Bobinski Purdue University Follow this and additional works at: https://docs.lib.purdue.edu/open_access_dissertations Part of the Organic Chemistry Commons Recommended Citation Bobinski, Thomas Paul, "Osmium Catalyzed Dihydroxylation And Oxidative Cleavage Of Vinyl Sulfone And Elucidation Of The Vinylsulfone Polypropionate Methodology For The yS nthesis Of The C32 eD s-Methyl C28-C34 Actin Binding Tail Of Aplyronine A" (2013). Open Access Dissertations. 199. https://docs.lib.purdue.edu/open_access_dissertations/199 This document has been made available through Purdue e-Pubs, a service of the Purdue University Libraries. Please contact [email protected] for additional information. Graduate School ETD Form 9 (Revised 12/07) PURDUE UNIVERSITY GRADUATE SCHOOL Thesis/Dissertation Acceptance This is to certify that the thesis/dissertation prepared By Thomas Paul Bobinski Entitled For the degree of Doctor of Philosophy Is approved by the final examining committee: Philip L. Fuchs Chair Paul Wenthold Mark Lipton Mahdi abu-Omar To the best of my knowledge and as understood by the student in the Research Integrity and Copyright Disclaimer (Graduate School Form 20), this thesis/dissertation adheres to the provisions of Purdue University’s “Policy on Integrity in Research” and the use of copyrighted material. Approved by Major Professor(s): ____________________________________Philip L. Fuchs ____________________________________ Approved by: R. E. Wild 9/26/2013 Head of the Graduate Program Date OSMIUM CATALYZED DIHYDROXYLATION AND OXIDATIVE CLEAVAGE OF VINYL SULFONE AND ELUCIDATION OF THE VINYLSULFONE POLYPROPIONATE METHODOLOGY FOR THE SYNTHESIS OF THE C32 DES-METHYL C28-C34 ACTIN BINDING TAIL OF APLYRONINE A A Dissertation Submitted to the Faculty of Purdue University by Thomas Paul Bobinski In Partial Fulfillment of the Requirements of the Degree of Doctor of Philosophy December 2013 Purdue University West Lafayette, Indiana ii ACKNOWLEDGMENTS I would like to thank all of the great and influential chemists that have been responsible for molding me into the scientist I am today. First and foremost I would like to thank my truly visionary genius advisor and labmate Philip Lorenz Fuchs. Under his influence I have learned to be critical of scientific data and more importantly myself. I was shown how to think about organic synthesis without the typical limitations so common among organic chemists today. Thanks to him I was able to contribute to a synthetic methodology that will have a greater impact on natural product synthesis for years to come. Seeing him work in the hood sharpened my own skills. The positive impact of my association with Professor Harry Morrison can not be overstated. I was Professor Morrison’s lecture TA from 2009-2012. I have never encountered a more precise communicator of the fundamental concepts of organic chemistry. Thanks to him, my understanding of physical organic concepts has increased exponentially due to my association with him. His continued mentorship and example he sets has inspired my scientific paradigm, not to mention he‘s really cool. I would be remiss if I did not recognize Dr. Jack Parson’s of Starks Associates, my first principle investigator after getting my masters degree. I can unabashedly declare that the core of my laboratory skills is due to the delightfully harsh and, “nose to the iii grindstone,” style of mentorship of Dr. Parsons. It was Professor Fuchs and Dr. Parson’s that made me one with the concept of, “all that matters is what you get in the bottle (vial),” everything else is window dressing. Mark Lipton’s unrivalled understanding of mechanistic concepts contributed to the first paradigm shift I experienced upon my arrival to Purdue University. Subsequent candid discussions with Professor Lipton about electron pushing, hyperconjugation, and even the tetrahedral nature of sulfones and sulfuric acid compelled me to call on him to be the first member of my advisory committee. I would like to thank the rest of my committee members Professor Abu-Omar and Wenthold. I owe my understanding of reaction kinetics to Professor Wenthold. My understanding of organo-metallics rests on the concepts taught by Professor Abu-Omar. iv TABLE OF CONTENTS Page LIST OF TABLES ................................................................................................. vi LIST OF FIGURES .............................................................................................. vii LIST OF SCHEMES ............................................................................................ xii LIST OF ABBREVIATIONS ................................................................................ xiv ABSTRACT ...................................................................................................... xviii CHAPTER 1: RATIONALE ................................................................................... 1 1.1: Biological Basis For Total Synthesis Of Aplyronine ................................... 1 1.2: Retrosynthetic Analysis Of Aplyronine Macrolactone Core ........................ 9 1.3: Polypropionate Generating Methodologies .............................................. 12 1.4: References ............................................................................................... 28 CHAPTER 2: THE VINYL SULFONE MOIETY AS A POLYPROPIONATE FACILITATOR .................................................................................................... 38 2.1: Use of Carbocyclic Scaffold in the VinylsulfonePolypropionate Strategy . 38 2.2: Dienylsulfone Asymmetry ........................................................................ 46 2.3: Epoxide Directed Asymmetry .................................................................. 47 2.4: Aluminoxane as a Nucleophilic Methylation Species .............................. 49 2.5: Differentiation of Termini Post Oxidative Cleavage ................................. 50 2.6: Formation of the , - Unsaturated Sulfone .............................................. 51 2.7: 1,4-Elimination of Sulfone with Trimethylaluminum .................................. 52 2.8: References ............................................................................................... 54 CHAPTER 3: DEVELOPMENT AND APPLICATION OF THE VINYLSULFONE POLYPROPIONATE METHODOLOGY ............................................................. 55 3.1: Large Scale Generation of Dienylsulfone ................................................. 55 3.2: VinylsulfonePolypropionate Algorithm ..................................................... 57 v Page 3.3: Application of Vinylsulfone Polypropionate Methodology The C5-C11 syn, anti, syn Blue Fragment ......................................................................... 58 3.4: Application of VinylsulfonePolypropionate Methodology C21-C27 Red, C28-C34 Green Fragments syn, anti, syn ....................................................... 61 3.5: References .............................................................................................. 65 CHAPTER 4: IN DEPTH EXAMINATION OF THE APLYRONINE ACTIN BINDING TAIL REGION .................................................................................... 68 4.1: Literature Methodologies ......................................................................... 68 4.2: C28-C34 Green Fragment Backbone Strategy 1st Generation ................. 76 4.3: C28-C34 Green Fragment Backbone Strategy 2nd Generation ................ 78 4.4: Surrogate Methodologies En Route to the C28-C34 Fragment ............... 81 4.5: The Stork-Sophia Strategy ...................................................................... 85 4.6: C28-C34 Green Fragment via a, “Pivot Strategy.” ................................... 90 4.7: References ............................................................................................... 97 CHAPTER 5: OXIDATIVE CLEAVAGE OF CYCLIC VINYLSULFONE ............ 100 5.1: Oxidative Cleavage of Cyclic Vinylsulfone Stereotetrads ....................... 100 5.2: Oxidative Cleavage of the Vinyl Sulfone – Ozonolysis ........................... 104 5.3: Dihydroxylation Via Established Methodology ....................................... 109 5.4: Citric Acid Catalyzed Dihydroxylation .................................................... 115 5.5: References ............................................................................................. 120 CHAPTER 6: C28-C34 STEREOTRIAD SYNTHETIC RAMIFICATIONS ....... 122 6.1: Assembly of Aplyronine A Backbone .......................................................... 122 6.2: Implications of C32 des-Methyl Stereotriad ........................................... 128 6.3: A Reexamination of the C21-C27 Fragment .......................................... 131 6.4: Further Evaluation of C21-C27 Strategies .................................................. 137 6.5: References ............................................................................................. 146 APPENDICES Appendix A- Experimental ............................................................................ 148 Appendix B- NMR Spectra ............................................................................ 175 VITA ................................................................................................................
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