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Tributyltin Mediated Radical Cyclizations of Enediynes and Their Subsequent Transformation to Fulvenes and Indenes Scott W

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Tributyltin Mediated Radical Cyclizations of Enediynes and Their Subsequent Transformation to Fulvenes and Indenes Scott W Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2004 Tributyltin Mediated Radical Cyclizations of Enediynes and Their Subsequent Transformation to Fulvenes and Indenes Scott W. Peabody 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 SCIENCE TRIBUTYLTIN MEDIATED RADICAL CYCLIZATIONS OF ENEDIYNES AND THEIR SUBSEQUENT TRANSFORMATION TO FULVENES AND INDENES By SCOTT W. PEABODY A Thesis submitted to the Department of Chemistry and Biochemistry in partial fulfillment of the requirements for the degree of Master of Science Degree Awarded: Summer Semester, 2004 The members of the Committee approve the Thesis of Scott W. Peabody defended on April 28, 2002. Dr. Igor Alabugin Professor Directing Thesis Dr. Gregory Dudley Committee Member Dr. Oliver Steinbock Committee Member Approved: Naresh Dalal, Chair, Department of Chemistry and Biochemistry The Office of Graduate Studies has verified and approved the above named committee members. ii This is dedicated to my family and to future wife. iii ACKNOWLEDGEMENTS The author wished to extend his sincere appreciation to Prof. Igor Alabugin, whose patience, guidance and support has been instrumental in all the work that I have conducted. I would further like to thank Dr. Serguei Kovalenko for his day in and day out dedication, supervision and instruction and Dr. Mariappan Manoharan for the computations included in this work. I would also like to thank CDR Richard Sanders, USCG, who gave me my first introduction into chemical research and who has served as a mentor over so many years. iv TABLE OF CONTENTS List of Tables .................................................................................... vi List of Figures .................................................................................... vii List of Schemes .................................................................................... xi Abstract .......................................................................................... xiv 1. Introduction .................................................................................... 1 A. Radical Reactions of Enediynes ............................................... 1 B. Selectivity of Radical Cyclizations............................................. 4 C. Tributyltin Hydride in Radical Reaction ..................................... 9 D. Reactions of Vinylstannanes..................................................... 13 2. Results and discussion...................................................................... 12 A. Synthesis of enediynes............................................................. 12 B. Tributyltin hydride mediated cyclization of diaryl enediynes...... 13 C. Limitations of tributyltin cyclization of enediynes....................... 18 D. Fulvenes as building blocks in organic synthesis..................... 21 E. Synthesis of Deuterated Fulvene and Indenes ......................... 24 3. Experimental .................................................................................... 30 1H and 13C NMR data..................................................................... 51 Crystal Structures........................................................................... 127 REFERENCES .................................................................................... 130 BIOGRAPHICAL SKETCH .................................................................... 134 v LIST OF TABLES 1. Absolute rate constants (k) for reaction of organohalides and alkenes with tributyltin radical. .................................................................................... 9 2. Absolute rate constants (k) for reaction of carbon-centered radicals with tributyl tin hydride. .................................................................................... 10 3. Sonogashira coupling results. ........................................................ 12 4. Energetics of the competing radical cascades in Scheme 8 at the UB3LYP level. .................................................................................... 16 5. The relative energies of α-and β-radicals formed from 1,2-diethynylbenzene and its diaryl derivatives, activation and reaction energies for 5-exo cyclization of β-radicals, difference in energies between the (E) and (Z)-isomers of fulvene products, and geometries of respective fulvene radicals at the UB3LYP6-31G**//3-21G* level. .................................................................................... 17 vi LIST OF FIGURES 1. Illustration of Beckwith Model chair-like transition state. ................ 5 2. Calculated spin density and geometry of fulvene radicals 23 (R=TFP) and 24 (R=Ph) at the UB3LYP/3-21G* level ..................................................... 18 3. 1H NMR of aromatic region of fulvene isotopomers ....................... 26 1 4. H NMR (300 MHz /CDCl3) of 1,2-Diiodo-4,5-dimethyl-benzene.... 51 13 5. C NMR (75.4 MHz/CDCl3) of 1,2-Diiodo-4,5-dimethyl-benzene .. 52 1 6. H NMR (300 MHz/CDCl3) of 1,2-Diiodo-4,5-dimethoxy-benzene.. 53 13 7. C NMR (75.4 MHz/CDCl3) of 1,2-diiodo-4,5-dimethoxy benzene 54 1 8. H NMR (300 MHz /CDCl3) of 13.................................................... 55 13 9. C NMR (75.4 MHz/CDCl3) of 13 .................................................. 56 1 10. H NMR (300 MHz /CDCl3) of 14.................................................... 57 13 11. C NMR (75.4 MHz/CDCl3) of 14 .................................................. 58 1 12. H NMR (300 MHz /CDCl3) of 15.................................................... 59 13 13. C NMR (75.4 MHz/CDCl3) of 15 .................................................. 60 1 14. H NMR (300 MHz /CDCl3) of 16.................................................... 61 1 15. H NMR (75.4 MHz/CDCl3) of 16.................................................... 62 1 16. H NMR (300 MHz /CDCl3) of 17.................................................... 63 13 17. C NMR (75.4 MHz/CDCl3) of 17 .................................................. 64 1 18. H NMR (300 MHz /CDCl3) of 18.................................................... 65 vii 13 19. C NMR (75.4 MHz/CDCl3) of 18 .................................................. 66 1 20 H NMR (300 MHz /CDCl3) of 20.................................................... 67 13 21. C NMR (75.4 MHz/CDCl3) of 20 .................................................. 68 1 22. H NMR (300 MHz /CDCl3) of 21.................................................... 69 13 23. C NMR (75.4 MHz/CDCl3) of 21 .................................................. 70 1 24. H NMR (300 MHz /CDCl3) of 22.................................................... 71 13 25. C NMR (75.4 MHz/CDCl3) of 22 .................................................. 72 1 26. H NMR (300 MHz /CDCl3) of 23.................................................... 73 13 27. C NMR (75.4 MHz/CDCl3) of 23 .................................................. 74 1 28. H NMR (300 MHz /CDCl3) of E-1-[(2,3,5,6-Tetrafluoropyridinyl) methylene]-2- (2,3,5,6-tetrafluoropyridinyl)-3-(tributylstannyl)-1H-indene ..................... 75 13 29. C NMR (75.4 MHz /CDCl3) of E-1-[(2,3,5,6-Tetrafluoropyridinyl) methylene]-2- (2,3,5,6-tetrafluoropyridinyl)-3-(tributylstannyl)-1H-indene ..................... 76 19 30. F NMR (282.4 MHz /CDCl3) of E-1-[(2,3,5,6-Tetrafluoropyridinyl) methylene]-2- (2,3,5,6-tetrafluoropyridinyl)-3-(tributylstannyl)-1H-indene ..................... 77 1 31. H NMR (300 MHz /CDCl3) of Z-1-[(2,3,5,6-Tetrafluoropyridinyl) methylene]-2- (2,3,5,6-tetrafluoropyridinyl)-3-(tributylstannyl)-1H-indene ..................... 78 13 32. C NMR (75.4 MHz /CDCl3) of Z-1-[(2,3,5,6-Tetrafluoropyridinyl) methylene]-2- (2,3,5,6-tetrafluoropyridinyl)-3-(tributylstannyl)-1H-indene ..................... 79 19 33. F NMR (282.4 MHz /CDCl3) of E-1-[(2,3,5,6-Tetrafluoropyridinyl) methylene]-2- (2,3,5,6-tetrafluoropyridinyl)-3-(tributylstannyl)-1H-indene ..................... 80 1 34. H NMR (300 MHz /CDCl3) of E-24 ................................................ 81 13 35. C NMR (75.4 MHz/CDCl3) of E-24............................................... 82 19 36. F NMR (282.4 MHz/CDCl3) of E-24 ............................................. 83 viii 1 37. H NMR (300 MHz/CDCl3) of Z-24 ................................................. 84 13 38. C NMR (75.4 MHz/CDCl3) of Z-24............................................... 85 19 39. F NMR (282.4 MHz/CDCl3) of Z-24 ............................................. 86 1 40. H NMR (300 MHz /CDCl3) of E-25 ................................................ 87 13 41. C NMR (75.4 MHz/CDCl3) ofE-25................................................ 88 1 42 H NMR (300 MHz /CDCl3) of E-26 ................................................ 89 13 43 C NMR (75.4 MHz/CDCl3) of E-26............................................... 90 1 44 H NMR (300 MHz /CDCl3) of E-27 ................................................ 91 45 13C NMR (75.4 MHz/CD6O) of E-27............................................... 92 1 46 H NMR (300 MHz /CDCl3) of E-28 ................................................ 93 13 47 C NMR (75.4 MHz/CDCl3) of E-28............................................... 94 1 48 H NMR (300 MHz /CDCl3) of E-29 ................................................ 95 13 49 C NMR (75.4 MHz/CDCl3) of E-29............................................... 96 1 50 H NMR (300 MHz /CDCl3) of E-30 ................................................ 97 13 51 C NMR (75.4
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