Transition metal chemistry ansd catalysis

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Our long-term research objective is to design and understand the functioning of new catalysts for bulk or fine chemical synthesis with applications in fragrance, flavours and pharmaceutical industries and catalysts for hydrogen storage, production or sensing for applications in the energy field. Over the past five years we have developed a variety of successful homogeneous catalysts and asymmetric catalysts based on ruthenium and osmium with hydride, phosphorus and nitrogen donor ligands. These are active for the selective hydrogenation of polar bonds including ketones for the production of alcohols and the hydrogenation of imines and nitriles for the synthesis of valuable amines. The same versatile catalysts are effective for asymmetric Michael addition reactions for fine chemical synthesis. This year we have discovered very active iron catalysts that are less expensive, less toxic and more environmentally friendly than ruthenium, rhodium or palladium catalysts. The iron catalysts will be a primary focus of the proposed research along with extensions of our ruthenium chemistry and exploratory work with other transition metals. Our successful approach to catalyst discovery involves the synthesis of well-defined complexes within or near to the postulated catalytic cycle and a careful study of their mode of action by measurement of rates and isotope effects, activation energies, and by ab initio calculations. An objective is relating the structure and electronics of the catalytic species with their activity and selectivity. Another objective is to improve the methods of synthesis and the properties of the catalysts to make them useful and easy to reuse. Such catalysts often have metal-hydrogen bonds. The protonic and hydridic reactivity of these compounds will continue to be studied in our lab in order to better understand catalysts and predict new chemical reactions.