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Durham E-Theses Durham E-Theses Studies of the synthesis and derivative chemistry of icosahedral carboranes Lane, Richard A. How to cite: Lane, Richard A. (1982) Studies of the synthesis and derivative chemistry of icosahedral carboranes, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/7680/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk STUDIES ON THE SYNTHESIS AND DERIVATIVE CHEMISTRY OF ICOSAHEDRAL CARBORANES A Thesis Submitted to The University of Durham by Richard A. Lane, B.Sc. (Hatfield College) For The Degree of Doctor of Philosophy July 1982 The copyright of this thesis rests with the author. No quotation from it should be published without his prior written consent and information derived from it should be acknowledged. To my parents ACKNOWLEDGEMENTS I wish to express my thanks to Dr. K. Wade under whose supervision the work was carried out at Durham University, for his patience and encouragement throughout the study. I am indebted to the Ministry of Defence, Aldermaston for the maintenance grant and in particular to Mr. W.A. Fort for making the whole project possible and his close liaison. I wish to thank all the members of the Chemistry Department at Durham University for their technical assistance especially Mr. B. Hall, and all my colleagues for their friendship and patience. Finally my most sincere thanks go to Mrs. Margaret da Cunha for the many exasperating hours spent deciphering and typing this thesis. MEMORANDUM The work described in this thesis was carried out by me in the Chemistry Department of the University of Durham between October 1977 and September 1980. I declare that this work has not been submitted for any other degree. This thesis is my original work, except where indicated by reference to other work. ABSTRACT As part of the general study of icosahedral carborane chemistry a comprehensive literature survey is presented with references. Investigations of the preparative routes to ortho-carborane, 1-methyl-o-carborane and some carborane polymers showed that improve• ments on existing literature methods could be made. In the synthesis of possible carborane-polymer precursors, several coupled carborane systems were investigated. These included C-C, B-B' direct cage coupling reactions and coupling via short alkyl chains. Reactions of Me6Li (9= -CB^QH^QC-) with boron chlorides produced the previously unreported boron coupled carboranes (Me6)2BR, (R = C1,0H, Ph) and MeSBPh^. Three carborane cages could not be bonded to a single boron atom. The previously unreported di-(3,3'-o-carboranyl)-N,N- piperazine was prepared from the anion. Studies were made of the reaction of Me0Li with ICK and (CN)2* An attempted ortho-metallation reaction with SnCl^, Me6Li and PhCN yielded an interesting dicyclic tin adduct, SnCl^. ^(PhCiO^^ • 2- The reactions of C^B^B.^ with tin, germanium and silicon tetrachlorides produced a new class of dicarboranyl metal "sandwich" compounds for which a novel tilted cage structure was proposed. Zinc metallocarboranes could not be synthesised. Hot atom chemistry was employed in attempts to prepare main group metalloaarboranes by polyhedral expansion. CONTENTS Page No. NOMENCLATURE 1 CHAPTER 1 LITERATURE REVIEW 1.1 INTRODUCTION 3 Structure and Bonding of Carboranes 3 Preparation and Properties of Icosahedral Carboranes 6 1.2 ALKALI METAL AND MAGNESIUM DERIVATIVES 10 Alkali Metal Derivatives 10 Magnesium Derivatives 11 1.3 ALKYL AND HALOALKYL PERIVATIVES 13 Synthesis of Alkyl Derivatives 13 Synthesis of Haloalkyl Derivatives 14 Reactions of Alkyl and Haloalkyl Derivatives 15 1.4 ALKENTL AND ALKYNYL DERIVATIVES 17 Synthesis of C-Alkenyl Derivatives 17 Synthesis of Alkynyl Derivatives 19 Reactions of C-Alkenyl Derivatives 20 Reactions of Alkynyl Derivatives 26 1.5 ARYL DERIVATIVES 29 Synthesis 29 Reactions of Aryl Carborane Derivatives 33 Page No. 1.6 CARBOXYLIC ACID AND ACID HALIDE DERIVATIVES 35 Synthesis of Carboranyl Carboxylic Acids 35 Reactions of Carborane Carboxylic Acids 40 1.7 ALCOHOL, ETHER AND ESTER DERIVATIVES 46 Synthesis of Alcohols 46 Synthesis of Ethers 50 Synthesis of Esters 51 Reactions of Alcohols 53 Reactions of Esters 54 1.8 ALDEHYDE AHD KETONE DERIVATIVES 56 Synthesis of Aldehydes 56 Synthesis of Ketones 57 Reactions of Aldehydes 60 Reactions of Ketones 61 1.9 HALOGEN DERIVATIVES 63 Electrophilic Substitution 63 Photochemical Halogenation 66 Fluorination 66 Synthesis from Halo-Decaborane(14) 67 Synthesis of 3-Halo-O-Carborane 67 C - Halo Derivatives 67 Reactions of Halogen Derivatives 68 1.10 NITROGEN DERIVATIVES 72 Synthesis of Amines 72 Reactions of Amino Derivatives 74 Synthesis of Amides 77 Page No. Cyano Derivatives 78 Nitrates and Related Derivatives 79 Other Nitrogen Derivatives 80 1.11 GROUP IV DERIVATIVES 82 Silicon Derivatives 82 Germanium, Tin and Lead Derivatives 85 1.12 GROUP V DERIVATIVES 88 1.13 GROUP VI DERIVATIVES 93 1 .14 SIGMA-BONDED TRANSITION METAL DERIVATIVES 97 Mercury Derivatives 97 1.15 POLYMER DERIVATIVES 104 Pendant Carborane Polymers 104 Chain Linking Carborane Polymers 106 1.16 CARBORANYL ANIONS AMD ICOSAHEDRAL HETBROATOM CAGES 113 Synthesis of Carboranyl Anions 113 Mono-carbon Carborane Anions 116 Icosahedral Mono-carbon Heteroatom Cages 117 Dicarbon Heteroatom Icosahedra 120 CHAPTER 2 PREPARATION OF ORTHO CARBORANE AND 1-METHYL ORTHO CARBORANE 2.1 INTRODUCTION 125 2.1.1 Reaction Scheme 126 2.1.2 Purification of Decaborane(14) 126 Page No. 2.1.3 Important Safety Note 132 2.1.4 Preparation of Bis-(acetonitrile)-Decaborane (12) 132 2.1.5 Preparation of 2-Butyne-1,4-Diacetate 134 2.1.6 Preparation of 1,2-Bis(acetoxymethyl)-0-Carborane 135 2.1.7 Preparation of Ortho Carborane from 1,2-Bis(acetoxymethyl)-0-carborane 137 2.1.8 Discussion 139 2.2 PREPARATION OF 1-METHYL ORTHO-CARBORANE 142 CHAPTER 3 COUPLED CARBORANE SYSTEMS 3.1 INTRODUCTION 144 3.2 CARBON-CARBON COUPLED 1,1'-BIS-CARBORANES 145 3.2.1 Introduction 145 3.2.2 Preparation of Butadiyne 145 3.2.3 Preparation of Bis-carborane by Two Stage Synthesis 146 3.2.4 Preparation of Bis-cartJorane by a Single Stage Synthesis 148 3o3 BORON-BORON COUPLED BIS-CARBORANES 150 3.3.1 Introduction 150 3.3.2 Preparation of 9-Iodo-O-Carborane 150 3.3.3 Reaction between 9-Iodo-O-Carborane and Cu in THF 151 3o3»4 Reaction between 9-Iodo-O-Carborane and Cu Powder at High Temperature 153 3.3.5 Reaction between 9-Iodo-O-Carborane and Lithium Amalgam 154 Page Ho. 3.4 ALKYL CHAIN COUPLED CARBORANES 156 3.4.1 Introduction 156 3.4.2 Reaction between Dilithio-m-Carborane and Dibromoethane 156 3.4.3 Reaction between 1-Methyl,2-Lithio-O-Carborane and Dibromoethane 158 3.4.4 Two Stage Alkyl Chain Coupling Reaction (a) Reaction between Dilithio-m-Carborane and 1,3-Dibromopropane 161 (b) Reaction of the Product of (a) with 1-Methyl,2-Litnio-O-Carborane 161 3.5 BORON COUPLED CARBORANES 163 3.5.1 Introduction 3.5.2 Reaction of 1-Lithio-O-Carborane with Boron Trichloride 163 3.5.3 Reaction of 1-Methyl,2-Lithio-O-Carborane and Boron Trichloride 166 3.5.4 Reaction of Diphenyl Boron Chloride with 1-Methyl,2-Lithio-O-Carborane 170 3.5.5 Reaction of Phenyl Boron Dichloride Lithio Methyl-O-Carborane 173 3.5.6 Conclusion 175 3.6 HETEROCYCLE COUPLED CARBORANES 177 3.6.1 Introduction 177 3.6.2 Preparation of 3-Carboranyl Piperidine 178 3.6.3 Reaction between C?B1nHl5 and Piperazine 180 Page No CHAPTER 4 CARBORANE POLYMERS 4.1 INTRODUCTION 184 4.2 PREPARATION OF DEXSIL 200 184 4.3 PREPARATION OF P0LY(VINYL-0-CARB0RANE ) 188 4.3.1 Preparation of Vinyl Acetylene 188 a) Method I 188 b) Method II 189 4.3.2 Preparation of 1-Vinyl-O-Carborane 190 CHAPTER 5 REACTION OF LITHIO-O-CARBORANES WITH CYANIDES 5.1 THE REACTIONS OF CYANOGEN COMPOUNDS WITH LITHIO-O-CARBORANES 193 5.1.1 Introduction 193 5.1.2 Preparation of Cyanogen Iodide 194 5.1.3 Reaction between ICN and 1-Lithio,- 2-Methyl-O-Carborane 195 5.1.4 Reaction between Cyanogen and 1-Lithio,— 2-Methyl-O-Carborane 198 5.1.5 Reaction between Silver (i) Cyanide and Iodo-1-Methyl-O-Carborane 199 5.1.6 Conclusion 201 5»2 REACTION OF 1-LITHI0. 2-METHYL-O-CARBORANE WITH BENZONITRILE AND TIN (IV) CHLORIDE 202 5.2.1 Introduction 202 CHAPTER 6 METALLOCARBORANES 206 6.1 INTRODUCTION Page No. 6.2 PREPARATION OF STARTING MATERIALS 210 6.2.1 Preparation of Dicarbollide Ion 210 a) Preparation of Trimethylammonium- 1, 2-dicarbaundecaborate(l2) 210 b) Preparation of Dicarbollide ion, C^B^R^ 211 2 6.3 REACTIONS OF C£B H^ " WITH TIN CHLORIDES 214 6.3.1 Reaction of Tin (IV) Chloride with Dicarbollide Ion in THF 214 6.3.2 Reaction of Tin (IV) Chloride with Dicarbollide Ion in Acetonitrile 214 + 6.3.3 Reaction of Tin(lV) Chloride with Tl TlCgHgRj1 215 6.3.4 Reaction of Tin (II) Chloride with Dicarbollide Ion 217 6.3»5 Results Comparison 218 6.4 REACTIONS OF C^IL <2 " COMPOUNDS WITH GERMANIUM (IV) CHLORIDE y 231 6.4.1 Introduction 231 6.4.2 Reaction of Germanium (iv) Chloride with Dicarbollide Ion in Acetonitrile 231 6.4.3 Reaction of Germanium (IV) Chloride with + _ Tl TlCgBgH^ in Acetonitrile 232 6.4.4 Results Comparison 233 6.5 REACTIONS OF C B H,/" COMPOUNDS WITH SILICONE IV) CHLORIDE y 240 6.5.1 Reaction of Silicon (iv) Chloride with + Tl TlC2BgH11 " 240 2- 606 REACTIONS OF C^B ^ 1 COMPOUNDS WITH ZINC (II) CHLORIDE 243 6.6.1 Introduction 243 6.6.2 Preparation of Zinc (II) Chloride 243 6.6.3 Reaction of Zinc (il) Chloride with Dicarbollide Ion in THF 244 Page No.
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