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At the University of Edinburgh This thesis has been submitted in fulfilment of the requirements for a postgraduate degree (e.g. PhD, MPhil, DClinPsychol) at the University of Edinburgh. Please note the following terms and conditions of use: This work is protected by copyright and other intellectual property rights, which are retained by the thesis author, unless otherwise stated. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. This thesis cannot be reproduced or quoted extensively from without first obtaining permission in writing from the author. The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the author. When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given. Iron and Nickel Complexes as Catalysts in CO2/Epoxide Coupling, Radical Polymerisation and Hydrocyanation Reactions Eszter Fazekas A thesis submitted at the University of Edinburgh for the Degree of Doctor of Philosophy 2018 Table of contents Table of Contents .................................................................................................................................... 2 Declaration .............................................................................................................................................. 5 Acknowledgements ................................................................................................................................. 6 Lay summary ........................................................................................................................................... 8 Abstract ................................................................................................................................................... 9 Publications ........................................................................................................................................... 10 Abbreviations ........................................................................................................................................ 11 Chapter 1 General introduction ........................................................................................................ 13 Chapter 2 Ligand development for hydrocyanation and isomerisation reactions.......................... 18 Introduction ...................................................................................................................................... 19 Hydrocyanation ............................................................................................................................. 19 Industrial relevance....................................................................................................................... 20 Definition of main ligand parameters ........................................................................................... 21 Mechanistic studies ...................................................................................................................... 22 DuPont adiponitrile process .......................................................................................................... 25 Critical evaluation ......................................................................................................................... 29 Aims .................................................................................................................................................. 30 Results and Discussion ...................................................................................................................... 31 Triptycene ligand............................................................................................................................... 31 Background ................................................................................................................................... 31 Synthesis of Triptycene ligand ...................................................................................................... 33 Tetraphenol ligands .......................................................................................................................... 35 Background ................................................................................................................................... 35 Synthesis of tetraphenol backbones ............................................................................................. 36 Synthesis of tetraphenol diphosphite ligands............................................................................... 38 Synthesis and characterisation of a tetraphenol-Ni complex ....................................................... 40 Catalytic activity of the TP2Ni complex in the ADN process ......................................................... 42 Biphephos ligand ............................................................................................................................... 47 Background ................................................................................................................................... 47 Hydrocyanation of styrene with Biphephos ligand ....................................................................... 49 Hydrocyanation of 1,3-butadiene with Biphephos ligand ............................................................ 51 Isomerisation of 2-methyl-3-butenenitrile with Biphephos ligand .............................................. 52 Hydrocyanation of 3-pentenenitrile with Biphephos ligand ........................................................ 56 2 Table of contents Summary and future work ................................................................................................................ 57 Experimental ..................................................................................................................................... 59 General considerations ................................................................................................................. 59 Synthesis of 1,8-difluoroanthraquinone ....................................................................................... 59 Synthesis of 1,8-difluoroanthracene ............................................................................................. 60 Synthesis of 1,8-difuorotriptycene ............................................................................................... 60 Synthesis of 1,8-diphenylphosphinotriptycene ............................................................................ 61 Synthesis of TP0 backbone ........................................................................................................... 61 Synthesis of TPB backbone ........................................................................................................... 62 Synthesis of TP2 ligand ................................................................................................................. 62 Synthesis of TP6 ligand ................................................................................................................. 63 Synthesis of TP7 ligand ................................................................................................................. 63 Synthesis of TP2Ni complex .......................................................................................................... 63 Synthesis of BIPPP ligand .............................................................................................................. 64 General procedure for hydrocyanation experiments ................................................................... 64 General procedure for 2M3BN isomerisation experiments ......................................................... 64 References ........................................................................................................................................ 65 Chapter 3 Iron half salen complexes: synthesis, characterisation and application in CO2/epoxide coupling ................................................................................................................................................ 69 Introduction ...................................................................................................................................... 70 Half salen ligands and complexes ..................................................................................................... 70 Synthesis of cyclic carbonates via CO2/epoxide coupling ................................................................. 72 Critical evaluation ............................................................................................................................. 81 Aims .................................................................................................................................................. 82 Results and discussion ...................................................................................................................... 83 Synthesis of half salen pro-ligands .................................................................................................... 83 Synthesis of FeIII half salen complexes .............................................................................................. 84 CO2/epoxide coupling reactions ....................................................................................................... 90 Summary and future work .............................................................................................................
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