This dissertation has been , 69-11,692 microfilmed exactly as received PECHHOLD, Engelbert, 1933- STUDIES OF THE BEHAVIOR AND GENERATION OF GARB ANIONS: PART I. INVERSION OF SECONDARY CYCLIC GRIGNARD REAGENTS. PART II. FRAGMENTATION OF AZOFORMATE SALTS AND ACYLAZO COMPOUNDS WITH BASES. The Ohio State University, Ph.D., 1968 Chemistry, organic University Microfilms, Inc., Ann Arbor, Michigan ©Copyright "by- Engelbert Pechhold 1969 STUDIES OF THE BEHAVIOR MD GENERATION OF CARBANIONS PART I. INVERSION OF SECONDARY CYCLIC GRIGNARD REAGENTS PART II. FRAGMENTATION OF AZOFORMATE SADIS AND ACYLAZO COMPOUNDS WITH BASES DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Engelbert Pechhold * # # * * # The Ohio State University 1968 Approved by •pV-gpa.-t— Adviser Department of Chemistry DEDICATION To my wife, Ingrid, and my parents, whose love, understanding, and encouragement have made this venture possible. ii ACKNOWLEDaEMElWS I -wish to express my deepest appreciation to Professor Gideon Fraenkel for suggestinf^ this problem, and for his guidance and encouragement throughout the course of this research. His assistance in the preparation of this dissertation is gratefully acknowledged. It is an understatement to say that without his un­ usual courage of conviction and high standards for academic perfor­ mance, this work could not have come into being. I owe special debt of gratitude to my colleagues for many suimtü-ating discussions of chemical matters and otherwise. In particular, I wish to express my gratitute to Dr. Don Dix, Dr. Dave Mams, and James Morton, who gave me much insight in ny research. I wish also to thank Dr. Ralph Dougherty for his advice and help in interprepreting the mass spectra, Furthermore, I wish to thank Dr. C. J. Pedersen of Du Pont Company who provided us with dicyclohexyl-18-crown-6, and Dr. K. Greenlee of Chemical Samples Company who supplied us with a few alicyclic hydrocarbons. The National Institutes of Health and the United States Air Force are thanked for research assistantships which provided financial support during the course of this work. iii VITA March 10, 1953 ...... Born - Maehr. Ostrau, Czechoslovakia 1953 ..................... Chemotechniker (B.S.), Chemotechnikum Fresenius, Wieshaden, Germany 1955“1962 ............... Research Chemist, Chemische Werke Albert, Wiesbaden, Germany 1962-1968 ............... Research Assistant, Department of Chemistry, The Ohio State University, Columbus, Ohio PIEIDS OF STUDY Major Field; Organic Chemistry Minor Field; Inorganic Chemistry Chemistry of Carhanions Professor Gideon Fraenkel iv TABLE OB’ COWTEHTS Page DEDICATION........................ i ACKNOWLEDGEMENT...................................... ü VITA .................................... iv TABLES................................................ vil ILLUSTRATIONS......... viii PART I CHAPTER I I. INTRODUCTION AND HISTORICAL REVIEW Historical Background .......................... 1 Previous Research................... Ij. II. PURPOSE AND METHOD OF RESEARCH ................. 6 CHAPTER II EXPERIMEIWAL I. CHEMICALS...................................... 8 II. IDENTIFICATION OF SYWDHESIZED COMPOUNDS.......... 9 III. SYKDHESES l-Bromo~3,3-dimethylcyclolDutane................. 10 1-Phenyl-3,5-dimethyIcyclohutanecarho%ylie acid . l4 l-Bromo-2, 2-dimethylcy dopent an e ............... l6 l-Bromo-2,2-dimethylcyclohexane................. I9 l-Bromo-3,3-dimethylcyclohexane................. 24 l-Bromo-4,4-dimethylcyclohexane................. 35 IV. EREPARAIIOW OF THE ORGMOMETAELIC COMPOIMDS Solvents, Metals............................... 2'9 ÏÏMR Sample Tubes.............................. 50 Instrumentation.............................. 30 Procedure for the Preparation of Organometallic Compounds.................................... 32 Grignard Reagents........... .......... 32 3,3-Dimethylcyclohutyllithium . ........... .35 CHAPTER III RESUITS Al® DISCUSSION Syntheses of Cyclic Bromides ....................... 3^ Grignard Reagents.................................. 43- General Considerations.... .......................... 42 BIBLIOGRAPHY........................... .5 3 PART II CHAPTER I I. INTRODUCTION AND HISTORICAL REVIEW Historical Background ......................... 55 Preparative Methods of Organometallic Compounds of Group lA-IITA..................... 56 II. PURPOSE AND METHOD OF R E S E A R C H ................. I. CHEMICALS...................................... 71 II. IDENDIFICATION OF SYNTHESIZED COMPOUITDS.......... 73 III. SYNTHESES Potassium Phenylazoformate..................... 7 j^ Benz oylphenyld i imide ............. ^......... 76 Phenyl-£-toluoyldiimide............ '.......... 77 (Dimethoxyphosphinyl ) phenyldiimide............. 77 Benzoyl-t-hutyldi imide......................... 7 ° Carhmethoxy-t-hutyldiimide ............. ^ Dicyclohexyl-lS-crovm-ô....................... °3 vi IV. FRAGMENTATION REACTIONS Decarboxylation of Potassium Phenyl­ azoformate ....................................... 86 General Procedure for the Base-catalyzed Fragmentation of Acylazo Compounds ............... 88 Fragmentations of Benzoylphenyldiimide.............89 Fragmentation of Phenyl-£-toluoyldiimide .......... 91 Fragmentations of Benzoyl-t-butyldiimide .......... 9^ V. REACTION OF t-BUTYLLITHIUM WITH METHYL BENZOATE Products .................................... .9 7 VI. METHYL BENZOATE(2 ,1^.,6-da) Preparation.................................... 105 Reaction with t-Butyllithium..................... 105 VII. REACTIONS OF COMPOUND X X X V I I ...................... .I06 CHAPTER III RESULTS AND DISCUSSION Syntheses of Azoformate Salts......................... 109 Decarboxylation of Azoformate Salts................... 110 Syntheses of Acylazo Compounds ................11^ Base-catalyzed Fragmentations of Acylazo Compounds . .11° Reaction of t-Butyllithium with Methyl Benzoate........ 130 BIBLIOGRAPHY.......................... 159 TABLES • Table No. Page 1 . Chemical Reagents, Part I ......................... 8 2 . Chemical Reagents, Part I I ........................ 71 3 * Fragmentation of Acylazo Compounds........... H 7 k. Fragmentation of Benzoyl- and £-Toluoylphenyl- diimide with Potassium Methoxide ................... 121 5. Fragmentation of Benzoyl-t-butyldiimide withSodium and Potassium Methoxide.............................122 6 . Products from the Reaction of Methyl Benzoate with t-Butyllthium........... ?-29 vxx ILLUSTRATIONS Figure Page 1 . Apparatus for Grignard and Organolithium Preparations ............ ......... 31 2 . Nmr Spectrum(6o MHz) of 3 ,)-Dimethylcyclobuty- magnesium Bromide, 1.5 M in Di g l y m e ................. 44 3 . Nmr Spectrum of 3 ,3-Dimethylcyclobutylmagnesium Bromide, Methyl Region, Expanded Scale............... 4-5 4-. Nmr Spectrum(6o MHz) of 2 ,2-Dimethylcyclopentyl- magnesium Bromide, Methyl Region ................ 46 5. Nmr Spectrum(6o MHz) of 2 ,2-Dimethylcyclohexyl- magnesium Bromide, Methyl Region, a) at 6o°, and b) at 1T0° .................................. 47 6. Nmr Spectrum(6o MHz) of 3 ,3-Dimethylcyclohexyl- magnesium Bromide, Methyl Region................... 48 7 . Nmr Spectrum(6o MHz) of 3 ,3-Dimethylcyclohexyl- magnesium Bromide. 1.4 M in D i g l y m e ......... 49 8. Nmr Spectrum(6o MHz) of 4 ,4-Dimethylcyclohexyl- magnesium Bromide. Methyl Region ................. 50 9. Nmr Spectrum(6o MHz) of 4 ,4-Dimethylcyclohexyl- magnesium Bromide as a Function of Temperature, Methyl Region, a) at75 ° b) at 175 °. c) at 200° . 51 10. Nmr Spectrum(6o MHz) of 3 ,3-Dimethylcyclobutyl- lithium, 1.3 M in B e n z e n e ......................... 5^ 11. Apparatus for the Fragmentation of Acylazo Confounds........................................ °5 12. Nmr Spectrum(6o MHz) of Q,-t-butylbenzyl- alcohol (XXXII ) ........" .............................i45 13. Nmr Spectrum(6o MHz) of l-Pivaloyl-4-t-butyl- cyclohexadiene-1 ,5 (XXXIII ) .........................l46 14 . Nmr Spectrum(6o MHz) of l-Pivaloyl-4-t-butyl- cyclohexadiene-2 ,5(XL), Vinyl Region ............... l47 15. Nmr Spectrum(6o MHz) of ,(%-Dimethyl-2-t-butyl- propiophenone (XXXIV ) .............................. l4 8 16. Nmr Spectrum(6o MHz) of Q:,of-Di-'t-butylbenzyl- alcohol(XXXV)............ 7 ........................l49 17. Nmr Spectrum(6o MHz) of a,c/-Di-t-butylbenzyl- alcohol-2 ,4 ,6-ds (XXXV-dg ). 7 ............. 150 18. Nmr Spectrum(60 MHz) of (j-p-Di-;fc-butylbenzyl- alcohol (XXXVI ) ............. ............ 151 19. Nmr Spectrum(60 MHz) of Compound X X X V I I .............. 152 20. Nmr Spectrum(lOO MHz) of Compound XXXVII after Decoupling of the Vinyl Pr o t o n s ............. 1 55 viii 21. Nmr Spectrum(6o MHz) of Compound XXXVII-dg........... 15^1- 22. Nmr Spectium(6o MHz) of Compound XKXVII-da........... 155 25. Nmr Spectrum(60 MHz) of Confound XL I I ............... 15^ 24. Nmr Spectrum(6o MHz) of Congound XXXVIII............. 157 25. Nmr Spectrum(60 MHz) of Compound XXXVIII-dg.......... 158 ix PART I CHAPTER I I. INTRODUCTION AND HISTORICAL REVIEW During the last decade the chemistry of organometallic compounds has undergone considerable progress and has become of great interest in the field of synthetic organic chemistry. Indeed, fundamental organometallic chemistry now represents one of the most fruitful sources of useful synthetic methods and mechanistic studies in the discipline of organic chemistry. The first preparation of an organometallic cong)ound was reported in l8k^ when Frankland (l) accidently