Gaining Selectivity Control in Homogeneous Catalytic Ester Formation and Reduction with Multi-Nuclear High Resolution FlowNMR Spectroscopy

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This research initially intends to look at Gusev's NNP catalyst and the reduction of methyl benzoate to benzyl alcohol with H2. In order to determine the catalytic cycle and kinetics, dynamic reaction monitoring techniques are being utilised; particularly FlowNMR which has the unique ability to find detailed and quantitative changes in the chemical nature of a homogeneous solution in real time and thus give the user the capability to identify intermediate species. With such information, one could design ideal conditions and/or catalysts to avoid inhibitive effects or catalyst deactivation.Already many questions exist relating to further understanding the mechanism of these pincer catalysts including: the effect of moisture which appears to be detrimental to the reaction, the apparent superiority of ethyl esters as substrates compared to others or the isomerisation of unsaturated substrates thought to be linked to catalyst deactivation. The use of FlowNMR presents a powerful tool with which these questions and others can be answered. I will be setting up hydrogenation reactions while taking live NMR measurements to allow me to calculate and analyse the chemistry of the reaction.The aims of the project are as follows:- Demonstrate high activity with Ruthenium pincer catalysts for ester hydrogenation; warranting replacement of traditional stoichiometric hydride reagents and thus bringing environmental and economic benefits.- Investigate catalytic mechanism for ester hydrogenation and transfer hydrogenation with detailed analysis using dynamic reaction monitoring / 1H and 31P FlowNMR spectroscopy.- Identify pathway and causes for catalyst deactivation.- Use acquired knowledge of reaction kinetics to optimise future reaction conditions and catalysts.