Title:
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Development of gold-catalysed reactions and C-H functionalisations
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This thesis is comprised of an introductory chapter, followed by four chapters outlining the research undertaken by the author throughout the duration of study. Chapter 1 provides an introduction to homogeneous gold(I) catalysis, focusing on the selective hydrofunctionalisation of 1,3-disubstituted allenes and in particular axial-to point chirality transfer. Chapter 2 describes the development of the first gold-catalysed intermolecular hydroalkoxylation of 1,3-disubstituted allenes to occur with excellent chirality transfer. The substrate scope and limitations of the reaction were investigated. A wide range of allenes and alcohols were shown to be suited to the reaction, with excellent chirality transfer achieved through prevention of the competing allene racemisation. Chapter 3 outlines the successful development of gold-catalysed hydroarylations of 1,3-disubstituted allenes. Excellent chirality transfer for the hydroarylation of allenes was achieved for the first time and the scope was extended to nucleophiles previously reported to be unsuited to the hydrofunctionalisation of 1,3-disubstituted allenes. Chapter 4 presents the first dual gold and photoredox catalysed aryl-aryl cross coupling which occurs through C-H activation. This work also constitutes the first gold-catalysed C(sp2)-H activation reaction which does not require stoichiometric oxidant. Chapter 5 details the development of a metal-, light- and photocatalyst free Minisci type alkylation procedure which is suitable for the late-stage C-H functionalisation of N-heteroarene and 1,4-quinone moieties, and uses cheap and readily available carboxylic acids.
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