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Mechanistic Studies in Carbene and Polyurethane Chemistry University of New Hampshire University of New Hampshire Scholars' Repository Doctoral Dissertations Student Scholarship Spring 2005 Mechanistic studies in carbene and polyurethane chemistry Susanne M. Lewis University of New Hampshire, Durham Follow this and additional works at: https://scholars.unh.edu/dissertation Recommended Citation Lewis, Susanne M., "Mechanistic studies in carbene and polyurethane chemistry" (2005). Doctoral Dissertations. 256. https://scholars.unh.edu/dissertation/256 This Dissertation is brought to you for free and open access by the Student Scholarship at University of New Hampshire Scholars' Repository. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of University of New Hampshire Scholars' Repository. For more information, please contact [email protected]. NOTE TO USERS This reproduction is the best copy available. ® UMI Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. MECHANISTIC STUDIES IN CARBENE AND POLYURETHANE CHEMISTRY BY SUSANNE M LEWIS B.A. Regis College, 1996 DISSERTATION Submitted to the University of New Hampshire in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy In Chemistry May, 2005 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 3169073 Copyright 2005 by Lewis, Susanne M. All rights reserved. INFORMATION TO USERS The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. ® UMI UMI Microform 3169073 Copyright 2005 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ALL RIGHTS RESERVED © 2005 Susanne M Lewis Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. This dissertation has been examined and approved. < J U Richard P. Johnson, Piafessor of Chemistry, Ph. D. / $ - . — — ^ Weinman, Professor of Chemistry, Ph. D. p -- ^ u £2 *_ P. Miller, Associate Professor of Chemistry, Edward H. Wong, Professor of ChenTishy, Ph. D. i t Yvon G. Durant, Research Associate Professor of Materials Science, Ph. D. r ( t o a r Date Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. DEDICATION This is dedicated to my husband, David, without whom I might never have gotten this far in pursuing my dream and to my father, who always wanted me to do my very best at whatever I did. IV Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGEMENTS I would like to thank the following: My major advisor, Richard Johnson, for all of his advice and guidance throughout my tenure in his laboratory. My committee members, Gary Weisman, Ed Wong, Glen Miller and Yvon Durant, for their consideration in reading my dissertation and providing me with additional insight. All of the professors I’ve had at UNH, Regis College, Wellesley College and U. Lowell for all of the knowledge they have given to me over the years. National Science Foundation, Non-lethal Technology Innovation Center, Future Faculty Fellowship from the Camille and Henry Dreyfus Foundation, UNH Graduate School and UNH Chemistry department for all the funding I have received. University Instrumentation Center for all of the training and advice I have received for much of the instruments I have been privileged to use. The Chemistry department staff, especially Cindi Rohwer and Peg Torch, for going the extra step in helping me through. My parents and family for all of their support while pursuing my degree. Marty Kociolek, for all of his advice and guidance during my first two years in graduate school. Everyone I’ve ever worked with, whether in the research lab, as fellow teaching assistants, in a course or just bouncing ideas off each other (you know who you are). And especially my husband, thanks. v Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS DEDICATION......................................................................................................................iv ACKNOWLEDGEMENTS........................ ......v LIST OF TABLES ................................................................... viii LIST OF FIGURES.................................................................................................... ix LIST OF SCHEMES............................................................................................................xii ABSTRACT . xvi CHAPTER PAGE I. PHOTOGENERATION OF REACTIVE CARBENES BY FRAGMENTATION OF CYCLOPROPANATED PHENANTHRENES ...........................................................1 Introduction ................................ ............................................ 1 Results and Discussion... .......................................................................... 6 Conclusion ................................................................................................................ 50 II. SYNTHESIS AND USE OF A NOVEL CATALYST FOR POLYURETHANE FORMATION AND ATTEMPTED MECHANISTIC DETERMINATION OF THE DABCO CATALYZED REACTION BETWEEN 1-HEXANOL AND P-TOLYL- ISOCYANATE.......................................................................... 52 Introduction .................................................................................................................. 52 Results and Discussion ................................................................................... 56 Conclusion . 79 vi Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. III. COMPUTATIONAL STUDIES OF THE INTERCONVERSION OF AXIAL TO EQUATORIAL METHYLCYCLOHEXANE................................................................. 81 Introduction ...........................................................................................................................81 Results and Discussion ...................................................................................................... 82 Conclusion .................................................................................................................... 8 6 IV. EXPERIMENTAL SECTION..................................................................................... 97 General Experimental ..........................................................................................................97 Experimental ........................................................................................................................ 100 LIST OF REFERENCES.......................... 138 APPENDIX 1................................................................................................. 143 APPENDIX 2 (on included CD) ........................................................................................ 256 vii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF TABLES TABLE PAGE 1. Molar Ratios of Reagents Used in Reaction Calorimetry Study ................................... 74 2. Rate Constants for Activated Isocyanate and Activated Alcohol Model Rate Laws...77 3. Experimental Error Determined from Using Average Rate Constants. Shaded areas indicate lower error. .......................................................................................................... 78 4. Energies Calculated Using HF/3-21G Level of Theory. ................................................ 8 8 5. Energies Calculated Using HF/6-21G* Level of Theory .............................................. 89 6 . Energies Calculated Using MP2/6-21G* Level of Theory... ......................................... 90 7. Difference Between Adjusted Relative Energies for HF/6-31G* and HF/3-21G .........95 8 . Difference between Adjusted Relative Energies for MP2/6-31G* and HF/6-21G*....96 viii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF FIGURES FIGURE PAGE 1. Stabilization of Carbene by Electron Donating Groups ................................ ................2 2. Examples ofNucleophilic, Ambiphilic and Electrophilic Carbenes ............................ 3 3. Computational Results for the Possible Mechanistic Pathways of Benzylchlorocarbene 1 0 4. Comparison of NMR Spectra for Photolysis of 7 in CDCI 3 (top) and CD 3 CN (bottom) 1 1 5. Symmetric and Antisymmetric Singlet Ground State Cyclopentyne Diradical 16 6 . Coupling Spin Systems for 3-Cyclopentenyl-l -cyclohexane (16) .......................... 23 7. Correllation Spectroscopy (COSY) for diene 16 at 360 MHz .....................................25 8 . Correllation Spectroscopy (COSY) for diene
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