Dr. Jason Martin Lynam
University of York
United Kingdom
An understanding of the mechanistic processes that underpin transition metal-catalysed reactions allows for the design of new catalysts and optimisation of reaction conditions with enhanced performance. A range of methods have been used to study reaction mechanism, however, the direction observation of bond cleaving and forming events underpinning a reaction is fraught with difficulty as the complexes that facilitate these steps are often present at low concentrations and are short lived. We have development a method, based on time-resolved infra-red spectroscopy on a ps-ms timescale, which employs a thermally inert, but photochemically activated, manganese carbonyl precatalyst to circumvent these problems. Irradiation simulates entry into the catalytic cycle and unique insight into key ligand coordination, bond formation and cleavage events can be directly obtained and quantified. Central to the strategy is the interplay between the experimental results and predictions made by density functional theory, giving detailed insight into the nature of the states involved in carbon-carbon bond formation.