Organocatalysis with N-heterocyclic carbenes via new reactive intermediates

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The following proposal describes studies focused on the potential of N-heterocyclic carbene (NHC) derived sulfinyl azolium intermediates in organocatalysis. The outcome of these will be the delivery of new and enantioselective, catalytic reactions as well as novel synthetic strategies to complex molecular structures. In 2009 it was discovered, that carboxylic acid oxidation state starting materials engage in Lewis base NHC catalysis via acyl azolium intermediates. The sulfonyl azolium intermediate was reported 2015 in a preliminary study by the Lupton group and has the potential to be exploited in an array of transformations mediated by NHCs. Based on these results, the principle aim is to develop the chemistry of its analogue, the sulfinyl azolium and related intermediates, and exploit the sulfinyl azolium in an enantioselective gamma-sultine synthesis. studies focused on the discovery of a one-pot, dual catalytic NHC annulation/Pd arylation will be undertaken to investigate potential utility of the sultine structures. Furthermore, studies towards annulative transformations of the sulfinyl azolium to beta-sultine products and finally, exploration of the chemistry of related sulfinyl azolium carbanions and allyl anions in reaction discovery will be undertaken. The studies detailed herein constitute an entry point to this yet unknown field which may well display significant diversity allowing a range of reaction designs to be realised.