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FSU ETD Template Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2017 Thermal Cycloisomerizations of 1,6-Enynes for the Synthesis of Illudinine and Other High-Value Polycyclic Aromatic Structures Alec Edouard Morrison Follow this and additional works at the DigiNole: FSU's Digital Repository. For more information, please contact [email protected] FLORIDA STATE UNIVERSITY COLLEGE OF ARTS AND SCIENCES THERMAL CYCLOISOMERIZATIONS OF 1,6-ENYNES FOR THE SYNTHESIS OF ILLUDININE AND OTHER HIGH-VALUE POLYCYCLIC AROMATIC STRUCTURES By ALEC EDOUARD MORRISON A Dissertation submitted to the Department of Chemistry and Biochemistry in partial fulfillment of the requirements for the degree of Doctor of Philosophy 2017 Alec Morrison defended this dissertation on April 10, 2017. The members of the supervisory committee were: Gregory B. Dudley Professor Directing Dissertation Thomas Miller University Representative Igor Alabugin Committee Member Kenneth Hanson Committee Member The Graduate School has verified and approved the above-named committee members, and certifies that the dissertation has been approved in accordance with university requirements. ii This work is dedicated to my family who has supported me through my entire academic career. iii ACKNOWLEDGMENTS I would like to thank Dr. Dudley for guiding me through the frustrations, setbacks, and successes of this academic journey which would not have been possible without him. I couldn’t have asked for a better advisor and am truly indebted to his patience and encouragements. Particular thanks go to my committee members for their helpful discussions, direction, and reminder of how much I have yet to learn, and to Tae for his endless advice. Thank you to JJ, Nick, Mélodie, Tristan and Gabe along with everyone else that I’ve had the pleasure of interacting with in the FSU chemistry department over the past few years. Finally, I would like to acknowledge my parents for constantly pushing me and helping me through my academic career and life, I don’t know how I will ever repay you. You are the real MVP. iv TABLE OF CONTENTS List of Schemes .............................................................................................................................. vi List of Tables ................................................................................................................................. ix List of Figures ..................................................................................................................................x Abstract .......................................................................................................................................... xi 1. Benzannulation ............................................................................................................................1 1.1 Introduction ..........................................................................................................................1 1.2 Metal-Catalyzed Cycloadditions ..........................................................................................3 1.3 Thermal, Photochemical, and Lewis Acid Promoted Benzannulation ..............................11 2. Dehydro-Diels-Alder Methodology for the Synthesis of Isoquinoline Derivatives and Polycyclic Chromophores ..............................................................................................................26 2.1 Thermal Cycloisomerization of Putative Allenylpyridines for the Synthesis of Isoquinoline Derivatives ................................................................................................................26 2.2 Solution and Solid-State Molecular Photophysics of gem-Dimethylcyclopentane Derivatives .....................................................................................................................................35 2.3 Triazabicyclodecene: An Optimized Reagent for Base-Mediated Isomerization of Alkynyl- to Allenyl-Pyridines in the Synthesis of Isoquinoline Derivatives ..................................43 2.4 Experimental Data .............................................................................................................51 3. Total Synthesis of Illudinine: A Densely Substituted Isoquinoline ..........................................75 3.1 Introduction ........................................................................................................................75 3.2 Results and Discussion ......................................................................................................82 3.3 Experimental Data .............................................................................................................89 Appendices .....................................................................................................................................96 A. 1HNMR and 13CNMR Spectroscopies for Chapter 2 ................................................................96 B. 1HNMR and 13CNMR Spectroscopies for Chapter 3 ..............................................................127 C. List of Experimental Terms ....................................................................................................134 References ....................................................................................................................................137 Biographical Sketch .....................................................................................................................155 v LIST OF SCHEMES Scheme 1. Inter- and Intramolecular Diels-Alder Reactions ...........................................................2 Scheme 2. Traditional Methods for the Synthesis of Polysubstituted Benzene Derivatives ...........3 Scheme 3. Metal-Catalyzed [2+2+2] Alkyne Cyclotrimerization ...................................................5 Scheme 4. CpCo(CO)2-Catalyzed [2+2+2] Cyclotrimerization ......................................................6 Scheme 5. Application of a CpCo(CO)2-Catalyzed [2+2+2] Cyclotrimerization to the Synthesis of Estrone .........................................................................................................................................7 Scheme 6. Pd-catalyzed [4+2] Benzannulation of Conjugated Enynes ..........................................8 Scheme 7. Proposed Mechanism of Pd-catalyzed [4+2] Benzannulation of Enynes and Diynes ...9 Scheme 8. Au(I)-Catalyzed Formal [4+2] Benzannulation of Enynes and Alkynes ....................11 Scheme 9. The Bergman Cyclization ............................................................................................12 Scheme 10. Application of the Bergman Cyclization to the Synthesis of Polyaromatics .............13 Scheme 11. Danheiser Benzannulation .........................................................................................15 Scheme 12. Application of First and Second-Generation Benzannulation Strategies to the Total Synthesis of (-)-Ascochlorin and Salvilenone ...............................................................................16 Scheme 13. Intramolecular [4+2] Benzannulations of Conjugated Enynes ..................................17 Scheme 14. Mechanism of the Intramolecular [4+2] Benzannulation of Conjugated Enynes .....19 Scheme 15. Dehydro-Diels-Alder Variants ...................................................................................19 Scheme 16. Dehydro-Diels-Alder Reaction of Styrene-Ynes .......................................................20 Scheme 17. Ueda and Johnson’s Alkyne-Diyne Dehydro-Diels-Alder Reaction .........................22 Scheme 18. The Hexadehydro-Diels-Alder Reaction ...................................................................23 Scheme 19. Application of the Hexadehyrdro-Diels-Alder Reaction to the Synthesis of Mahanimbine .................................................................................................................................24 Scheme 20. Identifying the Reactivity Limits of Malonate-Tethered Diynylpyridine 111 ..........26 vi Scheme 21. Classical (left) and Recent (right) Approaches to the Isoquinoline Core ..................29 Scheme 22. Central Hypothesis and Experimental Design ...........................................................30 Scheme 23. Tandem Fragmentation/Olefination Methodology for the Synthesis of 1,6-Enynes .31 Scheme 24. Synthesis of Phenylthio-enyne Substrates and Tandem (Cyclo)Isomerization / Elimination .....................................................................................................................................32 Scheme 25. Expanding the Benzannulation Scope through Further Synthetic Elaboration .........34 Scheme 26. Synthesis of Pentacyclic Phenanthridine 146 ............................................................36 Scheme 27. Synthesis Strategy for gem-Dimethylcyclopentane-Fused Arenes ............................37 Scheme 28. Synthesis of Dichloroanthracene and Dibenzo[g,p]chrysene Derivatives .................38 Scheme 29. Synthesis of Triphenylene 151 ..................................................................................39 Scheme 30. Diverging Pathways for the Synthesis of Naphthalene and Phenanthrene Derivatives ....................................................................................................................................40 Scheme 31. Proposed Mechanistic Pathways ................................................................................44 Scheme 32. Deuterium-labeling Experiments
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