Abstract
Exploring Ligand Effects in Exogenous-Oxidant-free Au(I)/Au(III) Catalysis investigates the design anddevelopment of gold complexes that can be used to catalyse redox reactions without the need for strong
exogenous oxidants. In this endeavour, exploration into the structural features necessary for a ligand to
facilitate oxidative addition to gold were undertaken.
The first chapter consists of an introduction into gold chemistry, with particular focus on redox gold
catalysis and literature examples of gold complexes undergoing oxidative addition with aryl iodides.
Chapter 2 describes the investigations into the ability of NHC gold(I) complexes to undergo oxidative
addition with synthetically interesting substrates, with emphasis into ligand design with hemi-labile
pendent donating groups. This resulted in the first example of successful oxidation of aryl iodides to a
gold(I) centre facilitated by an NHC ligand, forming stable (κ2-C,N) gold(III) aryl complexes. Electronic
and mechanistic investigations revealed unique behaviours in the oxidation of gold compared to other
literature known examples.
Further developing the initial observations within Chapter 2, Chapter 3 discusses the use of NHC
gold(I) complexes with hemi-labile groups as pre-catalysts for redox chemistry. The gold catalysed
1,2-difunctionalisation of highly abundant feedstocks is reported in the oxyarylation of ethylene and
propylene using a wide range of aryl iodides and alcohols. In addition to C–C and C–O forming
reactions, N-arylation of anilines is also described.
Chapter 4 explores the capacity of (P,N) ligands with enamine/imine functionalisation to facilitate
oxidative addition of aryl iodides to gold. In doing so, synthesis of the corresponding (P,N) gold(I)
complexes were achieved, and tautomerisation of the gold(I) and gold(III) complexes investigated.
Initial exploration into using these complexes in gold redox catalysis was conducted.
| Date of Award | 25 Jan 2022 |
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| Original language | English |
| Awarding Institution |
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| Supervisor | Chris A Russell (Supervisor) & George R Whittell (Supervisor) |