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The Synthesis and Coordination Chemistry of Functionalised and Macrocyclic Phosphines and Arsines THE SYNTHESIS AND COORDINATION CHEMISTRY OF FUNCTIONALISED AND MACROCYCLIC PHOSPHINES AND ARSINES by Matthieu Limon Submitted in fulfilment of the requirements of the Degree of Doctor of Philosophy Sehoot of Chemistry Cardiff University Wales, UK 2009 The work described in this thesis was carried out in the Department of Chemistry at The University of Wales Cardiff under the supervision of Prof. Peter G. Edwards UMI Number: U585156 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. Dissertation Publishing UMI U585156 Published by ProQuest LLC 2013. Copyright in the Dissertation held by the Author. Microform Edition © ProQuest LLC. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 Declaration This work has not previously been accepted in substance for any degree and is not being concurrently submitted in candidature for any degree. Signed Dated ^-3 Statement 1 This thesis is being submitted in partial fulfilment of the requirements for the degree of PhD. Signed.... Dated Statement 2 This thesis is the result of my own investigations, except where otherwise stated. Other sources are acknowledged by footnotes giving explicit references. A bibliography is appended. Signed Dated Statement 3 I hereby give consent for my thesis, if accepted, to be available for photocopying and for inter-library loan, and for the title and summary to be made available to outside organisations. Signed Dated Abstract The results presented in this thesis are separated into three distinct sections. Chapter 2 describes the reaction of the manganese precursors [Mn(OTf)(CO) 3{o-C6H4(PH2)2}]/ 2.6, and [Mn(OTf)(CO)3 {C2H4 (PH2)2 }L 2.7, with a silver carbene transfer agent, 1,3-dialtylbenzimidazol- 2-ylidiene, 2.10, to give the new phosphido-phosphine manganese species 2.11 and 2.12. The resultant species 2.11 and 2.12 exist in two geometric forms, c/s and trans, which have been characterised by X-Ray crystallography for 2.11. A new chiral rigid phospholane ligand 3(/?)-hydroxy-phenylphospholane, 3.7, has been prepared from the reaction of phenylphosphine with enantiopure (/?)-2-(oxiran-2-yl)ethyl-4- methylphenylsulfonate, 3.4. In order to enlarge the family of heterocyclic coordinated complexes, we herein report in Chapter 3 the synthesis of compounds [Mo(k-PR#s-3.7)2(CO)4], 3.16, [Re(CO)5(k-PR,s-3.7)], 3.17, [Mn(OTf)(CO)4(k-PR,s-3.7)], 3.18, [Ru(cymene)CI(k-PR,s-3.7)], 3.19, [FeCp'(CO)2(k-PR,s-3.7)]PF6, 3.20, [Rh(cod)CI(k-PR/S-3.7)], 3.21, c/s-[(k-PR,s-3.7)2PtCI2], 3.22, c/s-[(k-PRfs-3.7)2PdCI2], 3.23. Finalty, Chapter 4 presents the synthesis of new tribenzannulated diarsine monophosphine macrocycle complexes prepared by a template method via dehydrofluorinative cyclisation of the di-ortho-fluorophenylbisarsinobenzene ligand with PhPH2 at [MnfCOfe]* or [Re(CO) 3 j+ templates. The new macrocycles formed may expand the scientific understanding about phosphorus and arsenic chemistry. In order to enlarge this knowledge, other ways to introduce diarsenic ligands; in our case l,2-bis(arsino)benzene, 4.a, on a metal centre were attempted on MnBr(CO)s, 4.2, Mn(OTf)(CO)5, 4.3, [Mn(CO)3(NCCH3)3]PF6, 4.4, [Mn(CO)3(ace)3]PF6, 4.5, ReBr(CO)5, 4.6, Mn(OTf)(CO)s, 4.7, [Cr(CO)3(NCCH3)3], 4.8, and [M o(CO)3(NCCH3)3], 4.9, precursors but no discrete complexes could be isolated and characterised. Contents CHAPTER 1 - INTRODUCTION 1 1.1 G enerals properties of phosphine ligands 6 1.1.1 Electronic factors 9 1.1.2 Stericfactors 10 1.1.3 Polydentate phosphines 11 1.2 A rsines 13 1.3 N-H eterocycliccarbenes NHC 15 1.3.1 General methods of preparing stable carbenes 17 1.3.2 Basicity and nucleophilicity of stable carbenes 19 1.3.3 Reactivity of stable carbenes 20 1.3.4 Carbene complexation 21 1.4 M acrocycles 22 1.4.1 Synthesis 23 1.4.1.1 Cycloaddition Reactions. 23 1.4.1.2 Template methods. 25 1.5 References 28 CHAPTER 2 - BRIDGING PHOSPHIDO-PHOSPHINO LIGANDS IN BIMETALLIC COMPLEXES 34 2.1 Introduction 35 2 .2 Results a n d discussion 39 2.2.1 Synthesis offac-tricarbonyl-bis-(l,2-phosphino)bromo-manganese (I) derivatives 2.3 and 2.4 39 2.2.2 Synthesis offac-tricarbonyl-bis-(l,2-phosphino)triflato-manganese(l) derivatives 2.6 and 2.7 42 2.2.3 Synthesis of free carbene2.9 and silver-carbene transfer agent2.10 45 2.2.4 Coordination chemistry ofNHC ligand2.9 or 2.10 to fac-tricarbonyt-bis-(l,2- phosphino)(L)manganese(l) (L= Br, OTf) derivatives2.6 or 2.7 47 2.3 Conclusion 56 2 .4 Experimental 57 2.4.1 Methods and materials 57 2.4.2 Syntheses 58 2.4.2.1 Synthesis of MnBrfCOMo-QH^PHzh}, 2.3. 58 2.4.2.2 Synthesis of MnBr(CO) 3{C2H4(PH2)2}, 2.4. 58 2.4.2.3 Synthesis of MnfOTfXCOMo-QH^PHzh}, 2.6. 59 2.4.2.4 Synthesis of MnfOTfHCOMCzH^PHzk), 2.7. 59 2.4.2.5 Synthesis of 2.11. 60 2.4.2.6 Synthesis of 2.12. 61 2.4.3 Crystallography 61 2.5 References 62 CHAPTER 3 - SYNTHESIS OF A NEW CHIRAL RIGID HYDROXYPHOSPHOLANE LIGAND AND ITS COORDINATION CHEMISTRY 64 3.1 Introduction 65 3.2 Results a n d discussion 68 3.2.1 Ligand synthesis 68 3.2.2 Coordination chemistry 77 3.2.2.1 Attempts to coordinate 3(/?)-hydroxy-phenylphospholane, 3.7, to [Mo(pip)2(CO)4], 3.8. 77 3.2.2.2 Attempts to coordinate 3(/?)-hydroxy-phenylphospholane, 3.7, to ReBr(CO)5, 3.9. 79 3.2.2.3 Coordination chemistry of 3(/?)-hydroxy-phenylphospholane, 3.7, with a manganese metal precursor. 80 3.2.2.4 Coordination chemistry of 3(/?)-hydroxy-phenylphospholane, 3.7, with Group 8 metal precursors 3.11 and 3.12. 84 3.2.2.5 Coordination chemistry of 3(fl)-hydroxy-phenylphospholane, 3.7, with a rhodium metal precursor. 89 3.2.2.6 Coordination chemistry of 3(R)-hydroxy-phenylphospholane, 3.7, with Group 10 metal precursors platinum and palladium. 92 3.3 Conclusion 98 3 .4 Experimental 99 3.4.1 Methods and materials 99 3.4.2 Syntheses 100 3.4.2.1 Synthesis of (S)-bromosuccinic acid, 3.2. 100 3.4.2.2 Synthesis of (S)-2-bromo-l,4-butanediol, 3.3. 101 3.4.2.3 Synthesis of (R)-2-(oxiran-2-yl)ethyl-4-methylphenylsulfonate, 3.4. 101 3.4.2.4 Synthesis of (R)-2-(2-iodoethyl)oxirane, 3.5. 102 3.4.2.5 Synthesis of phenylphosphine, 3.6. 102 3.4.2.6 Synthesis of 3(/?)-hydroxy-phenylphospholane, 3.7. 103 3.4.2.7 Preparation of [Mo(k-PR>s-3.7)2(CO)4], 3.16. 104 3.4.2.8 Preparation of [ReBr(CO)4(k-PR<s-3.7)], 3.17. 104 3.4.2.9 Preparation of [Mn(CO)5(k-PR>s-3.7)]OTf, 3.18. 104 3.4.2.10 Preparation of [Ru(cymene)CI(k-PR/S-3.7)J, 3.19. 105 3.4.2.11 Preparation of [FeCp/(CO)2(k-PR/S-3.7)]PF6,3.20. 106 3.4.2.12 Preparation of [Rh(cod)CI(k-PR^-3.7)], 3.21. 107 3.4.2.13 Preparation of c/s-[(k-PR#s-3.7)2 PtCI2], 3.22. 108 3.4.2.14 Preparation of c/s-[(k-PRjS-3.7)2 PdCI2], 3.23. 108 3.4.3 X-ray Crystal Structure Analyses 109 3.5 References 110 CHAPTER 4 - TRIBENZANNULATED MIXED ARSINO-PHOSPHINO MACROCYCLES COMPLEXES BY TEMPLATE SYNTHESIS 112 4 .1 Introduction 113 4 .2 Results a n d discussion 117 4 .2 .1 Synthesis of a tribenzannulated 9-membered diarsino-monophosphino macrocycle based on the fac-tricarbonylmanganese template by method 1 117 4.2.2 Synthesis of a tribenzannulated 9-membered diarsino-monophosphino macrocycle based on the fac-tricarbonylmanganese template by method 2 119 4.2.3 Synthesis of a tribenzannulated 9-membered diarsino-monophosphino macrocycle based on the fac-tricarbonylrhenium template by method 1 127 4.2.4 Synthesis of a tribenzannulated 9-membered diarsino-monophosphino macrocycle based on the fac-tricarbonylrhenium template by method 2 128 4.2.5 Synthesis of a tribenzannulated 9-membered diarsino-monophosphino macrocycle based on the fac-tricarbonylchromium and the fac-tricarbonylmolybdenum template by method 1 131 4 .3 Conclusion 133 4 .4 Experimental 134 4.4.1 Methods and materials 134 4.4.2 Syntheses 135 4 .4 .2 .1 Synthesis of [Mn(CO) 3{(o-C6H4 F)2AsC6H4As(o-C6H4F)2}(NCCH3)] PF6/ 4.8. 135 4 .4 .2 .2 Synthesis of [Mn(CO)3{(o-C6H4F) (CeH4) As (CeHj As (CeH4) (o- QH4F)HP(C6H5)}]PF6,4.11. 135 4.4.2.3 Synthesis of [Re(OTf)(CO)3{(o-C6H4F)2As(C6H4)As(o-C6H4F)2}]/ 4.16.
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