This project in the Inorganic, Bioinorganic and Organometallic Chemistry Program is in the area of organometallic chemistry and is concerned with how transition metal oxo complexes are formed and how they react. Metal oxides and oxo compounds are widely used as catalysts and as reagents for selective transformations of organic compounds, but little is known about the mechanisms of most of these important processes. A major focus of the project is the interconversion of alkoxide and oxo-alkyl complexes. This 1,2-migration will be explored in a number of systems in order to understand the magnitude and origin of the kinetic barriers and to determine the migratory aptitudes of hydride, alkyl, phenyl, allyl and other groups. In a second subproject studies of oxygen atom transfer will probe the wide range of stability and reactivity of metal-oxygen multiple bonds. Oxygen atom transfer reactions will be used to address how multiple bond strengths vary with the nature of the metal, its oxidation state, and the ancillary ligands. This thermodynamic understanding of oxygen atom transfer will be coupled with mechanistic studies, with an emphasis on understanding the (often sizeable) kinetic barriers to atom transfer. Also to be explored is how oxo complexes are formed from dioxygen and related molecules, with special emphasis on the possibility of four-electron oxidative addition reactions.
