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Reactive Intermediates in the Anodic Oxidation of Cycloalkanecarboxylates

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Reactive Intermediates in the Anodic Oxidation of Cycloalkanecarboxylates Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1969 Reactive Intermediates in the Anodic Oxidation of Cycloalkanecarboxylates. Ernest Green Ed. Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Green, Ernest Ed., "Reactive Intermediates in the Anodic Oxidation of Cycloalkanecarboxylates." (1969). LSU Historical Dissertations and Theses. 1591. https://digitalcommons.lsu.edu/gradschool_disstheses/1591 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. This dissertation has been microfilmed exactly as received I GREEN, Ernest Ed, 1940- j 1 REACTIVE INTERMEDIATES IN THE ANODIC 1 OXIDATION OF CYCLOALKANECARBOXY- j LATES. j The Louisiana State University and j Agricultural and Mechanical College, Ph.D., 1969 Chemistry, organic University Microfilms, Inc., Ann Arbor, Michigan Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. REACTIVE INTERMEDIATES IN THE ANODIC OXIDATION OF CYCLOALKANECARBOXYLATES A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Chemistry Ernest E?% Green B.S., Louisiana Polytechnic Institute, 19^3 M.S., Louisiana Polytechnic Institute, I965 May, 1969 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGEMENT The encouragement, inspiration, careful guidance, and staunch support provided by Professor James G. Traynham in his capacities as advisor and research director is gratefully acknowledged. The complete faith and confidence shorn by the author's wife, Linda Ledbetter Green, made easier the long path through this research. Sincere appreciation and acknowledgement is made to the Charles E. Coates Memorial Fund for financial aid for expenses incurred in the presentation of parts of this dissertation research at Regional American Chemical Society meetings and in the preparation of this manuscript. Acknowledgement is also made of the financial support pro­ vided throughout the author's career in graduate school by Louisiana State University and the National Science Foundation. ii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS Page ACKNOWLEDGEMENT ...................................... ii LIST OF TABLES ...................................... vii LIST OF FIGURES .............. viii LIST OF SCHEMES .............. ix ABSTRACT ......... .......................... x CHAPTER I. INTRODUCTION ................................. 1 II. RESULTS AND DISCUSSION ...................... 11 III. CONCLUSIONS .......................... 36 IV. EXPERIMENTAL A. Deuterium Labeling of Cycloalkanecarboxylic Acids 1. G -Deuteriocyclohexanecarboxylic Acid . 42 2. G -Deuteriocyclooctanecarboxylic Acid . 44 3. G-Deuteriocyclononanecarboxylic Acid . 44 4. G-Deuteriocyclodecanecarboxylic Acid . 44 B. Kolbe Electrolyses of a-Deuteriocyclo- alkanecarboxylic Acids 1. General 46 2. G-Deuteriocyclohexanecarboxylic Acid . 47 3. G-Deuteriocyclooctanecarboxylic Acid . 49 4. O-Deuteriocyclononanecarboxylic Acid . 50 5. G-Deuteriocyclodecanecarboxylic Acid . 51 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. iv TABLE OF CONTENTS (Continued) Page CHAPTER IV. EXPERIMENTAL (Continued) C. Preparations and Reactions of t^Butyl Cyclooctaneperoxycarboxylates ..... 1(a). Preparation of Cyclooctanoyl C h l o r i d e ............ 52 1(b). Preparation of Cf-Deuterio- cyclooctanoyl Chloride ........... 53 2. Preparation of Sodium jt-Butyl- p e r o x i d e .......................... 53 3(a). Preparation of b-Butyl Cyclo- octaneperoxycarboxylate ......... 54 3(b). Preparation of _t-Butyl Q -Deuterio- cyclooctaneperoxycarboxylate ... 55 4 (a) . Thermal Decomposition of _t-Butyl . Cyclooctaneperoxycarboxylate ... 55 4(b). Thermal Decomposition of jt-Butyl fl-Deuteriocyclooctaneperoxy- carboxylate . ........... 56 D. Miscellaneous Control Experiments 1. Attempted Hydration of Cyclooctene . 57 2. Attempted Dehydration of Cyclooctanol 57 3. Attempted Base-Catalyzed Cf-Hydrogen- Deuterium Exchange . ............. 57 4. Electrolysis of Cyclooctanecarboxylic Acid in Binary S olvent ............. 58 5. Isotope Effect Studies in the Elect­ rolysis of d-Deuteriocyclooctane- carboxylic Acid versus Cyclooctane­ carboxylic Acid ............... 58 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. V TABLE OF CONTENTS (Continued) Page CHAPTER IV. EXPERIMENTAL (Continued) E. The Hunsdiecker Reaction 1(a). Preparation of Silver Cyclooctane- carboxylate ................. 59 1(b). Preparation of Silver Cf-Deuterio- cyclooctanecarboxylate ............... 60 2 (a). Reaction of Bromine and Silver Cyclooctanecarboxylate ............... 60 2(b). Reaction of Bromine and Silver G-Deuteriocyclooctanecarboxylate . 61 F. Dicyclooctylmercury Preparation and Decompositions 1. Preparation of Grignard Reagent from Cyclooctyl Chloride ................. 62 2. Preparation of Cyclooctylmercuric Bromide ................. 62 3. Preparation of Sodium Stannite .... 63 4. Preparation of Dicyclooctylmercury . 63 5(a). Decomposition of Dicyclooctylmercury in Water-tj-Butyl Alcohol ........... 64 5(b). Decomposition of Dicyclooctylmercury in W a t e r .............................. 64 APPENDICES I. Analytical Determination of Extent of Deuterium Rearrangement in Products Derived from Specifically Labeled Compounds........................... 65 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. vi TABLE OF CONTENTS (Continued) Page APPENCICES (Continued) II. Nuclear Magnetic Resonance Chemical Shifts of Cyclopropane HCH in Unsubstituted Bicyclo[x.l.O]- alkanes as a Function of Ring S i z e ............ 67 REFERENCES TO THE LITERATURE ............ '............ 68 SELECTED BIBLIOGRAPHY .............. 71 VITA ............................................... 72 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF TABLES Table Page I. Electrolyses In Water Of Cl-Deuteriocycloalkane- carboxylates .................................. 12 II. Relative Proportions Of Products From Electrolysis .................................. 13 III. Thermal Decompositions Of t-Butyl Cyclooctane- peroxycarboxylate In Binary Solution, H 20- ■ t-BuOH ................. 26 IV. Thermal Decomposition Of Dicyclooctylmercury . 31 vii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF FIGURES Figure Page 1. Electrolysis Apparatus ............................. 45 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF SCHEMES Scheme Page 1. (medium ring carbonium ion r e a ctions)........... 16 2. (medium ring radical reactions) ................. 18 3. (medium ring radical reactions with 02 ) ......... 19 4. (Hunsdiecker reaction)........................... 22 5. (decomposition pathways of peroxy esters) .... 24 6. (base catalyzed decomposition of dialkylmercury compounds)...................................... 33 7. (acid catalyzed decomposition of dialkylmercury compounds)...................................... 34 8. (cyclooctyl radical reactions in water) ......... -35 9. (overall reaction mechanism of anodic oxidation of cyclooctanecarboxylate in water). ...... 37 ix Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ABSTRACT Anodic oxidation of an aqueous solution of a cycloalkane- carboxylate (Kolbe electrolysis) generally leads to a mixture of products including cycloalkane, cycloalkene, bicycloalkane, cycloalkanol, dimer, and cycloalkyl cycloalkanecarboxylate. The prevailing view of the mechanism of this reaction attributes the formation of the oxygenated products, i.e., cycloalkanol and cycloalkyl ester, and the elimination products, i.e., cycloalkene and bicycloalkane, to carbonium ion processes. This dissertation research probes the significance of other product forming pathways, specifically those involving cycloalkyl radicals, to the overall delineation of the mechanism of the Kolbe electrolysis. The conclusions are based on both product studies and deuterium labeling experiments on transannular- rearrangement-prone medium ring systems.. Anodic oxidation of a-deuteriocycloalkanecarboxylates yielded the same products as the corresponding undeuterated compounds in the same relative amounts. Nmr analysis of the cycloalkanols and cycloalkenes from each reaction showed that more transannular rearrangement of the deuterium label had occurred in the processes leading to cycloalkanol than to cycloalkene, with the maximum discrepancy noted in the cyclooctyl case. Thermal decomposition, in aqueous solution , of tybutyl cyclooctaneperoxycarboxylate and dicyclooctylmercury, led, almost certainly via cyclooctyl radicals, to cyclooctane, cyclooctene, and unexpectedly, to cyclooctanol. x Reproduced with
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