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Development of a Synthetic Pathway Toward a Bowl-Shaped C 27H12 Polycyclic Aromatic Hydrocarbon

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Development of a Synthetic Pathway Toward a Bowl-Shaped C 27H12 Polycyclic Aromatic Hydrocarbon Graduate Theses, Dissertations, and Problem Reports 2013 Development of a Synthetic Pathway Toward a Bowl-Shaped C 27H12 Polycyclic Aromatic Hydrocarbon Yang-Sheng Sun West Virginia University Follow this and additional works at: https://researchrepository.wvu.edu/etd Recommended Citation Sun, Yang-Sheng, "Development of a Synthetic Pathway Toward a Bowl-Shaped C 27H12 Polycyclic Aromatic Hydrocarbon" (2013). Graduate Theses, Dissertations, and Problem Reports. 5004. https://researchrepository.wvu.edu/etd/5004 This Thesis is protected by copyright and/or related rights. It has been brought to you by the The Research Repository @ WVU with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you must obtain permission from the rights-holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/ or on the work itself. This Thesis has been accepted for inclusion in WVU Graduate Theses, Dissertations, and Problem Reports collection by an authorized administrator of The Research Repository @ WVU. For more information, please contact [email protected]. Development of a Synthetic Pathway Toward a Bowl-Shaped C27H12 Polycyclic Aromatic Hydrocarbon Yang-Sheng Sun Thesis submitted to the Eberly College of Arts and Sciences at West Virginia University in partial fulfillment ofthe reqmrements for the degree of Master of Science in Chemistry Kung K. Wang, Ph. D., Chair Jeffrey L. Petersen, Ph.D. Bjorn C. Soderberg, Ph. D. Department of Chemistry Morgantown, West Virginia 2013 Keywords: Enyne-Ailene, Schmittel Cyclization, Buckybowl Copyright 2013 Yang-Sheng Sun ABSTRACT Development of a Synthetic Pathway Toward a Bowl-Shaped C27H12 Polycyclic Aromatic Hydrocarbon Yang-Sheng Sun Bowl-shaped and basket-shaped polycyclic aromatic hydrocarbons (PAHs) have attracted considerable attention in recent years. They are challenging targets for total synthesis due to the presence of substantial strain energy in the curved structures. A solution-phase synthesis of a bowl-shaped polycyclic aromatic hydrocarbon Cz7H 12 was explored. The use of the casecade radical cyclization reactions of a benzannulated enyne-allene is a key feature of this synthetic pathway. The mild reaction conditions provide efficient and flexible designs for bowl- shaped and basked-shaped P AHs and their precursors. Our proposed synthesis strategy for the bowl-shaped Cz1H12 involves an initial synthesis of a benzannulated enediynyl propargylic alcohols followed by the cascade cyclization reactions of the resulting enyne-allenes. The use of the palladium-catalyzed intramoleular arylation reactions is proposed as a key step leading to the final products. Specifically, transformation of 1-indanone to a key intermediate, 2-methoxy-2-(2- methoxyethyl)-1-indanone, was extensively investigated, and the conditions for forming 1-(2- ethynylphenyl)-2-(2,6-dichlorophenyl)ethyne via the Sonogashira reaction were established. Condensation between the 1-indanone and the ethyny1 derivatives produced the benzannulated enediynyl propargylic alcohol. Chlorinated PAHs as potential precursors leading to the bowl- shpaed Cz1H12 hydrocarbon have been successfully synthesized. DEDICATED TO My Parents Jin-que Fang and Si-yan Sun iii ACKNOWLEDGEMENTS I would like to express my sincere gratitude to my advisor Dr. Kung Wang for his guidance, encouragement, and continuous support. He has inspired and advised me to grow intellectually and technically in organic research areas. He has never ceased to teach and inspire me to be a better scientist and person. I am very proud and grateful to be his student. I am grateful to my advisory committee, Dr. Jeffrey L. Petersen and Dr. Bjorn C. Soderberg for their advice, patience, and kindness. My special thanks go to Dr. Novruz Akhmedov for his help and support in NMR and Mass Spectroscopy. I acknowledge the financial support of the Department of Chemistry at West Virginia University. I would also like to thank my group members, past and present, for their support and friendship. Particularly I am indebted to Mr. Chi-Yuan Tseng for his help and valuable discussions in the lab. I thank my parents and my wife, Hui-Ju Hung, and my daughter Christine for their everlasting love and encouragement. Without their unconditional support, I could not come this far. iv TABLE OF CONTENTS Tit! e page ............................................................................................... i Abstract.. ............................................................................................... ii Dedication ............................................................................................. iii Acknowledgement ................................................................................... .iv Table of Contents ......................................................................................v List of Schemes ....................................................................................... vi List of Figures ........................................................................................vii List of Tables ........................................................................................ vii List of 1H and 13C NMR Spectra ................................................................vii Chapter 1 PRELUDE ........................................................................................... l 1. Introduction ...................................................................................................................... 1 2. Literature survey for the synthsis ofbuckybowls ............................................................ 4 3. Research objecive .......................................................................................................... 17 4. Results and dicussion ..................................................................................................... 21 5. Conclusion .................................................................................................................... 29 6.References .......................................................................................... .30 Chapter 2 EXPERIMENT SECTION .............................................................. 32 Experimental Methods ....................................................................................................... 32 Appendix ............................................................................................. 42 Approval of Examining Committee .............................................................. 74 v LIST OF SCHEMES Scheme 1 Synthesis pathways of corannulene by Barth and Lawton ........................ .4 Scheme 2 Corannulene prepared by FVP pathways ............................................... .4 Scheme 3 Other fullerene fragments prepared by FVP ........................................... 5 Scheme 4 Larger fragments prepared by FVP .............................................................. 6 Scheme 5 Synthesis of dimethylcorannulene by the Siegel group .............................. 7 Scheme 6 Improved synthetic procedures by Rabideau's group .................................... 7 Scheme 7 Palladium-catalyzed formation of buckybowls ...................................... 8 Scheme 8 Hirao's synthesis of sumanene ................................................................ 9 Scheme 9 Sakurai's synthesis of chiral sumanene ............................................................ ! 0 Scheme 10 Schmittel cyclization reaction ........................................................ ! 0 Scheme 11 Twisted polycyclic compounds synthesized via benzannulated enyene- allenes ................................................................................................ 11 Scheme 12 An alternative synthetic pathway for twisted polycyclic aromatic hydrocarbons ...................................................................................................................... 11 Scheme 13 Synthesis ofbuckybowls 1.52 and 1.55 via benzannulated enyne-allenes ..... 12 Scheme 14 Synthesis of the basket-shaped hydrocarbon 1.57 ................................ 14 Scheme 15 Synthesis of the basket-shaped hydrocarbon 1.58 ................................ 15 Scheme 16 Synthesis ofPAH 1.56 ................................................................ 18 Scheme 17 Alternative synthetic pathway to the bowl-shaped PAHs 1.67 ................. 19 Scheme 18 Attempted synthesis of 1-indanone 1.80 .......................................... .22 Scheme 19 Synthesis of 1-indanone 1.85 ........................................................ 23 Scheme 20 Synthesis of 1-indanone 1.80 ........................................................23 Scheme 21 Attempted synthesis of 1-indanone 1.85b ......................................... 24 Scheme 22 Synthesis of benzannulated enediyne 1.83 ........................................ .25 Scheme 23 Synthesis of 1.96a-c ...................................................................26 Scheme 24 Synthesis of compound 1.97 ........................................................................... 27 Scheme 25 Synthesis of compound 1.98a and 1.98b ........................................... 27 Scheme 26 Synthesis ofPAHs 1.99 and 1.100 ................................................. .28 vi LIST OF FIGURES Figure 1 End cap of a nanotube ...............................................................................
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