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Electrophilic Displacement Reactions: Part I Kinetics and Mechanism of The University of New Hampshire University of New Hampshire Scholars' Repository Doctoral Dissertations Student Scholarship Spring 1965 ELECTROPHILIC DISPLACEMENT REACTIONS: PART I KINETICS AND MECHANISM OF THE BASE AND METAL ION CATALYZED PROTODEBORONATION OF ARENEBORONIC ACIDSPART II: KINETICS AND MECHANISM OF THE PROTONOLYSIS OF TRIALKYLALLYLTINS JOHN ANDRE MANGRAVITE Follow this and additional works at: https://scholars.unh.edu/dissertation Recommended Citation MANGRAVITE, JOHN ANDRE, "ELECTROPHILIC DISPLACEMENT REACTIONS: PART I KINETICS AND MECHANISM OF THE BASE AND METAL ION CATALYZED PROTODEBORONATION OF ARENEBORONIC ACIDSPART II: KINETICS AND MECHANISM OF THE PROTONOLYSIS OF TRIALKYLALLYLTINS" (1965). Doctoral Dissertations. 815. https://scholars.unh.edu/dissertation/815 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]. This dissertation has been ... , „ . j 66—5973 microiumed exactly as received MANGRAVITE, John Andre, 1939- ELECTROPHILIC DISPLACEMENT REACTIONS: PART I; KINETICS AND MECHANISM OF THE BASE AND METAL ION CATALYZED PRO- TODEBORONATION OF ARENEBORONIC ACIDS. PART II; KINETICS AND MECHANISM OF THE PROTONOLYSIS OF TRIALKYLALLYLTINS. University of Now Hampshire, Ph.D., 1965 Chemistry, organic University Microfilms, Inc., Ann Arbor, Michigan Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ELECTROPHILIC DISPLACEMENT REACTIONS PART I: KINETICS AND MECHANISM OF THE BASE AND METAL ION CATALYZED PROTODEBORONATION OF ARENE- BORONIC ACIDS PART II: KINETICS AND MECHANISM OF THE PROTONOLYSIS OF TRIALKYLALLYLTINS BY / JOHN ANDRE MANGRAVITE B. S., Saint Peters College, 1961 A THESIS Submitted to the University of New Hampshire In Partial Fulfillment of The Requirements for the Degree of Doctor of Philosophy Graduate School Department of Chemistry June, 1965 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. This thesis has been examined and approved. ■ .i . L - L 1.1.. / / Director of Thesis Research / -'_____ _ Date Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGEMENT I should like to express my sincere thanks to Dr. Henry G. Kuivila whose help and guidance during the course of this research has proven invaluable to myself, both professionally and personally. I should also like to thank the Air Force Office of Scientific Research for their support of this research under contract AF 49 (638)-312, and the Atomic Energy Com­ mission for their support under contract AT(30-1)-2970. r ----------- TT- Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. To Mom and Dad Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS Page PART I LIST OF TABLES......... viii LIST OF FIGURES.................................... x INTRODUGTION...................................... 1 RESULTS AND DISCUSSION............................. 4 I. BASE-CATALYZED PROTODEBORONATION OF ARENEBORONIC ACIDS................ /, 1. Course of the reaction................... 4 2. Reaction system......................... 6 3. Kinetic order of the reaction............. 6 4. Effect of pH............................ 8 5. Effect of buffer concentration........... 11 6. Effect of substituents................... 16 7 . Mechanism............................... 19 8. Conclusion.............................. 28 II. METAL ION-CATALYZED PROTODEBORONATION OF ARENE­ BORONIC ACIDS............................... 35 1. Course of the reaction................... 35 2. Reaction system......................... 35 3. Kinetic order of the reaction............. 36 4. Effect of cadmium ion.................... 36 5. Effect of pH............................ 36 6. Effect of substituents................... 39 7. Effect of other metal ions............... 43 8. Mechanism............................... 48 9. Conclusion.............................. 57 EXPERIMENTAL...................................... 61 I. MATERIALS.................. 61 1. Water................................... 61 2. Areneboronic acids...................... 61 3. Malonic acid............................ 61 4. Sodium hydroxide........................ 61 5. Perchloric acid......................... 61 6. Sodium perchlorate.......... 61 7. Metal salts............................. 61 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. P a g e II. GLASSWARE CLEANING PROCEDURE................ 62 III. pH MEASUREMENT............................. 62 IV. BUFFERS.................................... 62 V. KINETIC PROCEDURE.......................... 62 1. Temperature control.................... 62 2. Base-catalyzed hydrolysis....... 62 3. Acid-catalyzed hydrolysis.............. 63 4. Metal ion-catalyzed hydrolysis......... 63 VI. CALCULATION OF RATE CONSTANT................ 63 BIBLIOGRAPHY............................... 64 TABLES OF DATA................................... 142 PART II LIST OF TABLES................................... 66 LIST OF FIGURES.................................. 67 INTRODUCTION..................................... 68 RESULTS AND DISCUSSION.................... 73 I. CLEAVAGE OF ALLYLTINS WITH HYDROGEN CHLORIDE 73 1. Synthesis of allyltins................. 76 2. Reaction system........................ 79 3. Course of the reaction................. 79 4. Kinetic procedure...................... 83 5. Kinetic treatment...................... 84 A. Aliquot method..................... 84 B. Direct method...................... 87 6. Substituent effects on the rate of cleavage of allyltins.................. 87 A. Structure of the leaving group...... 95 B. Substitution on the allyl group..... 97 C. Cyclic allyltins................... 101 7. Effect of added metal ions............. 103 II. CLEAVAGE OF ALLYLTINS WITH DEUTERIUM CHLORIDE 110 1. Starting materials..................... 110 2. Course of the reaction................. 110 3. Kinetic deuterium isotope effect....... 117 III. MECHANISM.................................. 125 vi Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Page EXPERIMENTAL..................................... 130 I. MATERIALS.................................. 130 1. Organotin substrates.................... 130 2. Hydrochloric acid....................... 134 3. Salts.................................. 134 4. Solvents............................... 134 5. Trimethyl tin chloride....................... 134 6. Deuterium oxide...’...................... 134 7. Methanol-d............................. 134 8. Deuterium chloride...................... 136 II. GLASSWARE CLEANING PROCEDURE................. 136 III. PRODUCTS OF CLEAVAGE........................ 136 IV. KINETIC PROCEDURES......................... 137 1. Aliquot method......................... 137 2. Direct method.......................... 138 BIBLIOGRAPHY..................................... 139 TABLES OF DATA................................... 142 Vll Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. PART I Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF TABLES Number Page I. Pertinent ultraviolet spectral-data for areneboronic acids; wavelengths used in analytical determinations............. II. Effect of boronic acid concentration on the rate of protodeboronation of 2,6-di- methoxybenzeneboronic acid at 90.0°C.... III. Effect of pH on the protodeboronation of 2,6-dimethoxybenzeneboronic acid in aqueous malonic acid-sodium malonate buffers at 90.0°C., and ionic strength 0.14......... IV. Effect of variation of malonate buffer con­ centration on the rate of protodeboronation of 2,6-dimethoxybenzeneboronic acid at 90.0°C., pH 6.70 and ionic strength 0.14,... 12 V. Variation of the rate of protodeboronation of 2,6-dimethoxybenzeneboronic acid with malonic acid concentration at 90.0°C., pH 3.60 and ionic strength 0.14; buffer ratio (H„A)/(HA) 0.155............................. :....... 13 VI. Values of kgxp. for the base-catalyzed proto­ deboronation of substituted benzeneboronic acids in aqueous malonic acid-sodium malonate buffers at 90.0°C., pH 6.70 and pH 6.42, and ionic strength 0.14........................ 17 VII. Relative specific rate constants in protode­ boronation of 2,6-dimethoxybenzeneboronic acids in aqueous malonic acid-sodium malonate buffers at 90.0°C., pH 6.70 and ionic strength 0.14...................................... 23 VIII. Relative specific rate constants in protode­ boronation of 2,6-dimethoxybenzeneboronic acid at 90.0°C............................ 34 Vlll Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Number Page IX. Effect of cadmium ion on the rate of proto­ deboronation of 2,6-dimethoxybenzeneboronic acid at 90,0°C., in I.00 x 10"^M perchloric acid.................................... 38 X. Effect of pH on the protodeboronation of 2, 6-dimethoxybenzeneboronic acid at 90.0°C. in perchloric acid, in the presence of 1.00 x 10“4m cadmium ion.......................... 42
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