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Asymmetric Homogeneous Hydrogenation Using Complexes of Rhodium(I) and Chiral Tertiary Phosphines

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Asymmetric Homogeneous Hydrogenation Using Complexes of Rhodium(I) and Chiral Tertiary Phosphines University of New Hampshire University of New Hampshire Scholars' Repository Doctoral Dissertations Student Scholarship Summer 1974 ASYMMETRIC HOMOGENEOUS HYDROGENATION USING COMPLEXES OF RHODIUM(I) AND CHIRAL TERTIARY PHOSPHINES WILLIAM F. MASLER III. Follow this and additional works at: https://scholars.unh.edu/dissertation Recommended Citation MASLER, WILLIAM F. III., "ASYMMETRIC HOMOGENEOUS HYDROGENATION USING COMPLEXES OF RHODIUM(I) AND CHIRAL TERTIARY PHOSPHINES" (1974). Doctoral Dissertations. 1056. https://scholars.unh.edu/dissertation/1056 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]. 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Xerox University Microfilms 300 North Zeeb Road Ann Arbor, Michigan 48106 74-27,978 MASLER, William F., III, 1947- asymmetric homogeneous hydrogenation using complexes OF RHODIUM (I) AND CHIRAL TERTIARY PHOSPHINES. University of New Hampshire, Ph.D., 1974 Chemistry, organic University Microfilms, A XEROX Company, Ann Arbor, Michigan THIS DISSERTATION HAS BEEN MICROFILMED EXACTLY AS RECEIVED. ASYMMETRIC HOMOGENEOUS HYDROGENATION USING COMPLEXES OF RHODIUM(I) AND CHIRAL TERTIARY PHOSPHINES by WILLIAM F. MASLER, III B. S., Bucknell University, 1969 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 July, 1974 This thesis has been examined and approved. Thesis Director, James D. Morrison Processor of Chemistry Paul R. Jones, Professor of Chemistry J./John Uebel, Professor of Chemistry k'km-ib James H. Weber, Professor of Chemistry ~l^'Upr^fL.l fx}'/cauAiPt, Miyoshi Tkawa, Professor of Biochemistry ijn\n Date ' ACKNOWLEDGEMENT The author wishes to express his appreciation to his research director, Dr. James D. Morrison, for the guidance, encouragement, and invaluable discussions during all phases of this work. The author expresses his apprec­ iation for the assistance rendered by the chemistry faculty and especially to Dr. K. K. Andersen, who served as second reader. Financial assistance in the form of a Water Resource Research Fellowship, Teaching Assistantships, a Research Fellowship from the Petroleum Research Fund administered by the American Chemical Society, and a National Science Foundation Fellowship is gratefully acknowledged. Sincere appreciation is expressed to John Penton, whose motorcycle provided the author with necessary escape from the laboratory. TO MY WIFE AND PARENTS TABLE OF CONTENTS LIST OF TABLES............................................... xiii LIST OF FIGURES.................................................xv ABSTRACT....................................................... xix INTRODUCTION..................................................... 1 HISTORICAL........................................................6 Mechanism of Reduction by Wilkinson's Catalyst........ 9 Scope of Reduction by Wilkinson's Catalyst............ 38 Asymmetric Reductions.................................... 45 RESULTS AND DISCUSSION. ..................................... 88 Synthesis of Chiral Phosphine Ligands..................89 Synthesis of (+)-Neomenthyldiphenylphosphine and (-) -Menthyldiphenylphosphine...................... 90 Synthesis of ( + )-CAMPHOS................................102 Asymmetric Homogeneous Hydrogenations.................125 EXPERIMENTAL................................................. ..166 General................................................... 166 Gas-Liquid Partition Chromatographic Analyses....... 166 Infrared Spectra......................................... 166 Nuclear Magnetic Resonance Spectra.................... 166 Elemental Analyses...................................... 166 Melting Points........................................... 170 Optical Rotations........................................170 Compounds.................................................170 Dry Solvents............................................. 170 v Hydrogenations........................................... 171 Gases..................................................... 171 Preparation of Ethyl Atropate......................... 172 Preparation of Atropic Acid from Ethyl Atropate 173 Preparation of (E) -a-Methylcinnamic Acid..............173 Preparation of (Z)-a-Methylcinnamic Acid by Photolytic Isomerization of (E)-a-Methyl­ cinnamic Acid ...................................... 174 Preparation of (E) -a-Phenylcinnamic Acid............. 175 Preparation of (Z)-a-Phenylcinnamic Acid by Photolytic Isomerization of (E)-a-Phenyl­ cinnamic Acid ...................................... 176 Preparation of Triethylphosphonoacetate.............. 176 Preparation of Ethyl-g-Methylcinnamate from Triethylphosphonoacetate and Acetophenone...... 177 Preparation of (E)-g-Methylcinnamic Acid by Hydrolysis of Ethyl-8-Methylcinnamate........... 178 Preparation of Ethyl-3-hydroxy-3-phenylbutanoate from Ethyl Bromoacetate and Acetophenone........ 178 Preparation of (E)-6-Methylcinnamic Acid from Ethyl- 3 -hydroxy- 3 -phenylbutanoate............... 179 Preparation of (Z)-6-Methylcinnamic Acid by Photolytic Isomerization of (E)- -Methyl- cinnamic Acid ...................................... 180 Preparation of Diphenylphosphine by Lithium Aluminum Hydride Reduction of Chlorodi- phenylphosphine.................................... 181 Preparation of (-)-Menthyl Chloride from (-)- Menthol............................................. 181 Preparation of (+)-Neomenthyldiphenylphosphine from (-)-Menthyl Chloride and Sodium Diphenylphosphide..................................182 Preparation of (+)-NMDPP Oxide by Oxidation of ( + ) -NMDPP........................................... 183 vi Preparation of (+)-NMDPP by Trichlorosilane Reduction of (+)-NMDPP Oxide..................... 184 Attempted Reduction of Neomenthyldiphenylphosphine Oxide by Hexachlorodisilane...................... 185 Attempted Lithium Aluminum Hydride Reduction of NMDPP Oxide........................................ 185 Preparation of Neomenthyldiphenylphosphine Sulfide from (+)-Neomenthyldiphenylphosphine Oxide 186 Preparation of (+)-Neomenthyl Chloride from (-)- Menthol............................................. 186 Preparation of (-)-Menthyldiphenylphosphine from (+)-Neomenthyl Chloride and Sodium Diphenyl- phosphide...........................................187 Preparation of (-)-MDPP Oxide by Oxidation of (-)-MDPP............................................189 Attempted Preparation of (-)-MDPP Oxide from (-)- Menthone and Diphenylphosphine.................. 18 9 Preparation of (-)-Menthyldiphenylphosphine by Trichlorosilane Reduction of (-)-MDPP Oxide............................................... 190 Preparation of (-)-Menthyldiphenylphosphine Sulfide from (-)-MDPP Oxide......... -............190 Preparation of (+)-1,2,2-Trimethyl-l,3-bis- (hydroxymethyl)cyclopentane by Lithium Aluminum Hydride Reduction of (+)-Camphoric A c i d .................................................191 Preparation of (+)-1,2,2-Trimethyl-l,3-bis- (hydroxymethyl)cyclopentane Ditosylate from (+)-1,2,2-Trimethyl-l,3-bis(hydroxymethyl)- cyclopentane........................................191 Preparation of (+)-CAMPHOS from 1,2,2-Trimethyl- 1,3-bis(hydroxymethyl)cyclopentane Ditosylate and Potassium Diphenylphosphide 192 Preparation of (+)-CAMPHOS Dioxide by Oxidation of ( + )-CAMPHOS.........................................193
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