Single-Molecule and Single-Active-Site Studies of Chirality Transfer and Olefin Metathesis Reactions on Metal and Metal Carbide Surfaces

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This research effort is based on the study of chemical reactions that take place on catalyst surfaces. These types of catalytic processes only take place rapidly when the reactant molecules encounter each other on custom-made catalyst surfaces. The Chinese characters for 'catalyst' can also be use for 'marriage broker'. Our research is aimed at understanding how the catalyst surface guides and activates the reactants-one couple at a time-towards a happy union. The guiding forces can range from the brutal to the subtle; the catalyst may need to split the reactants into fragments before the reaction occurs or it may simply need to induce reaction on one specific face of a molecule, as in a chiral reaction. We use a combination of surface science research tools to interrogate the forces that govern the reactivity of molecules in contact with a catalyst surface. These techniques are able to isolate single active sites on the surface and are able observe the organization of individual molecules around these sites. We collaborate with Danish scientists in the interpretation of the data. The projects are centred on two families of reactions, chiral or asymmetric catalysis and olefin metathesis. Chiral catalysis is central to the synthesis of pharmaceutical and agrochemical products. Olefin metathesis is an extraordinarily effective Green Chemistry method for the preparation of molecular materials. The molecular details gleaned from these studies are of primary importance to progress in many other areas than catalysis. This is because solid surfaces are used as literally the foundation of many modern technologies such as sensors and nanodevices. The chemical forces governing catalytic activity often also govern the quality of function of such devices.