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Cascade Reactions for the Synthesis of Polycyclic Aromatic Hydrocarbons and Carbon Nanoribbons Philip M

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Cascade Reactions for the Synthesis of Polycyclic Aromatic Hydrocarbons and Carbon Nanoribbons Philip M Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2013 Cascade Reactions for the Synthesis of Polycyclic Aromatic Hydrocarbons and Carbon Nanoribbons Philip M. Byers Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] THE FLORIDA STATE UNIVERSITY COLLEGE OF ARTS AND SCIENCES CASCADE REACTIONS FOR THE SYNTHESIS OF POLYCYCLIC AROMATIC HYDROCARBONS AND CARBON NANORIBBONS By PHILIP M. BYERS A Dissertation submitted to the Department of Chemistry and Biochemistry in partial fulfillment of the requirements for the degree of Doctor of Philosophy Degree Awarded: Summer Semester, 2013 Philip Byers defended this dissertation on June 17, 2013. The members of the supervisory committee were: Igor V. Alabugin Professor Directing Dissertation Rufina Alamo University Representative Geoffrey Strouse Committee Member Sourav Saha 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 To Loretta Jacqueline Jahoda Your patience, love and strength are an inspiration to me every day. iii ACKNOWLEDGMENTS This body of work would not have been possible without the support and guidance of my professors, peers, friends and family. After moving from western New York to Tallahassee in 2008, it has been a blessing to meet so many amazing people that have helped me succeed in my graduate career at Florida State. I would like to acknowledge my advisor, Professor Igor V. Alabugin, for accepting me into his group and supporting me during my research at FSU. Without his teachings and advice, the discoveries made during my graduate career would not have been possible. I have also had the opportunity to work with a number of amazing research scientists in my lab that helped shape me into the scientist I am today. I am grateful to Dr. Raja Angamuthu, Dr. Samuya Roy, Dr. Nikolay Shevchenko, Dr. Sergei Emets, Dr. Sayantan Mondal, Dr. Kishore Pati and especially Dr. Runa Pal who helped train me when I first joined the group. I would also like to recognize my labmates current and past, Dr. Jason Abrams, Dr. Wang-Yong Yang, Dr. Kerry Gilmore, Dr. Paul Peterson, Brian Gold, Kemal Kaya, Rana Mohamed, Trevor Harris, Audrey Hughes and Matthew Dickman. They have made coming to the lab every day an enjoyable experience. I have also had the opportunity to meet and learn from a number of great scientists at FSU. I would like to especially recognize Dr. Marilda Lisboa, Dr. David Jones, Dr. Umesh Goli, Dr. Tania Houjeiry, Steven Freitag, Michael Rosana, and Dr. Tyler Simmons for great technical and academic discussions. The undergraduate researchers that worked with me were also very influential in the success of my projects, including Julian Rashid, Ilya Piskun, Vekarius Barnes, Sheeva Yazdani, Artem Bobylev and Audrey Smith. I also have had the opportunity to meet a number of amazing people in Tallahassee who made my time here unforgettable, especially Jessica McBride, Kyle Rininger, Catherine Callahan, and pretty much the whole crew over at Momo’s pizza. Most importantly I have to thank my family, Richard and Kimberly, and my sisters Lindsay and Jessica, who without their support financially and otherwise, this would not have been possible. Thank you for your unwavering belief in me throughout my graduate career and all of my endeavors. iv TABLE OF CONTENTS List of Tables ................................................................................................................................ vii List of Figures .............................................................................................................................. viii Abstract ...................................................................................................................................... xviii 1. INTRODUCTION TO RADICAL CASCADE REACTIONS ...............................................1 1.1 Radical Cascades ...........................................................................................................1 1.1.1 Cascade Reactions by Chain Radical Processes ...............................................1 1.1.2 Radical Cascade Reactions Involving Non-Chain Redox Processes ................9 2. POLYAROMATIC RIBBONS FROM OLIGO-ALKYNES VIA SELECTIVE RADICAL CASCADE: STITCHING AROMATIC RINGS WITH POLYACETYLENE BRIDGES ..........14 2.1 Background ..................................................................................................................14 2.2 Enediyne Synthesis and Radical Cascades ..................................................................17 2.3 Tetrayne Synthesis and Radical Cascades ...................................................................23 2.4 Conclusion and Future Work .......................................................................................26 3. ELECTROPHILE-PROMOTED NUCLEOPHILIC CLOSURE CASCADE REACTIONS THROUGH GOLD CATALYSIS .................................................................................................29 3.1 Introduction ..................................................................................................................29 3.2 Examples of Gold Catalysis used for Cascade Reactions ............................................31 3.3 Examples of Gold Catalyzed Hydroarylation Reactions .............................................36 3.4 Synthesis of Polycyclic Aromatic Hydrocarbons through Gold Catalyzed Cascade Reactions Initiated by Hydroamination Cyclizations ............................................................40 4. GOLD CATALYSED CASCADE REACTION OF ENEDIYNES AND TRIYNE FOR THE SYNTHESIS OF FUSED BENZOFURAN POLYCYCLIC AROMATIC HYDROCARBONS ......................................................................................................................45 4.1 Introduction ..................................................................................................................45 4.2 Gold Catalyzed Cascade of Enediynes and Triyne ......................................................45 4.3 Conclusions ..................................................................................................................53 5. FUTURE WORK AND CONCLUSIONS ............................................................................54 5.1 Future Work ..................................................................................................................54 5.2 Conclusions ..................................................................................................................60 APPENDICES ...............................................................................................................................62 v A. EXPERIMENTAL DETAILS FOR RADICAL CASCADE (CH. 2) ..................................62 B. COMPUTATIONAL COORDINATES FOR RADICAL CASCADE (CH. 2) ...................73 C. NMR SPECTRA OF STARTING MATERIALS AND CASCADE PRODUCTS (CH. 2) .........................................................................................................................................116 D. EXPERIMENTAL DETAILS FOR GOLD CATALYZED CASCADE AND OPTIMIZED COORDINATES OF 21 (CH. 4) .................................................................................................165 E. NMR SPECTRA OF STARTING MATERIALS AND CASCADE PRODUCTS (CH. 4) .........................................................................................................................................178 REFERENCES ............................................................................................................................217 BIOGRAPHICAL SKETCH .......................................................................................................227 vi LIST OF TABLES 1 Computational analysis of enediyne cascade (B3LYP/6-31+ (d, p)), kcal/mol. ..............22 2 Optimization of the catalyst system. ................................................................................49 3 Tandem Sonogashira/cascade of substituted enediynes. .................................................50 vii LIST OF FIGURES 1 Stereoselective radical cascade as a key step in the construction of AB rings of azadirachtin. .........................................................................................................................3 2 Intermolecular iodine atom transfer cascades of alkynes to form vinyl iodides. ................4 3 Access to polycyclic indoles by radical addition/cyclization. .............................................5 4 O-neophyl rearrangement/fragmentation cascade for the conversion of phenols into benzoates and benzamides. ..................................................................................................6 5 Radical cyclization strategies to access complex polycyclic frameworks. ..........................8 6 Radical/aldol sequence from dialdehyde compounds using SmI2. ....................................10 7 Carbodiazenylation of alkenes from aryldiazonium salts using TiCl3. ..............................11 8 Mn(III)-promoted 5-exo/6-endo radical cyclization reactions. .........................................12 9 B3LYP calculated barriers for radical cascade transformation of tris-o- aryleneethynylenes via selective intermolecular activation. .............................................15 10 Proposed extension of the alkyne radical cascade towards longer graphene ribbons and importance
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