Organometallic and inorganic chemistry: design, synthesis, and mechanistic study of homogeneous catalysts for alkane oxidation, olefin hydroamination, a-olefin polymerization; metal-ligand structure-reactivity relationships; low coordinate metal-oxo complexes.
The catalytic, selective functionalization of simple chemical building blocks such as alkanes and alkenes under mild conditions represents an intellectual and technological challenge whose applications span from the cost-effective production of both bulk and fine chemicals to the development of new polymeric materials based on simple organic repeat units. Key to these processes are very often transition metal complexes which impart heightened reactivity, regioselectivity, and/or stereoselectivity when compared with uncatalyzed reactions.
With an ultimate goal of delveloping new homogeneous catalysts, we use synthetic organometallic and inorganic chemistry to probe transition metal complexes bearing relevant metal-bound functional groups. Through independent synthesis, species both inside and outside the catalytic cycles may be identified as well as modified, and stoichiometric transformations may potentially be rendered catalytic through a detailed understanding of the reactive metal complexes at hand.
A general theme that runs throughout each project is the development of appropriate coordination environments by using specifically designed ancillary ligands. Control over the steric and electronic environment of the relevant functional groups is essential to achieve the desired reactivity, as well as to approach the more subtle issues of regio- and stereoselectivity. Furthermore, once a promising class of ligands has been identified, in some instances the catalyst can be optimized using specially adapted combinatorial techniques.
Group members can expect to gain a great deal of experience in the synthesis and characterization of reactive, air-sensitive transition metal complexes. To facilitate the handling and exploration of these compounds, much of our synthesis work is carried out in a nitrogen filled glove box in which purified solvents are "on tap" and standard bench techniques such as vacuum filtration and rotary evaporation can be used. In addition, we employ single crystal X-ray crystallography as well as a wide variety of solution techniques such as IR, multinuclear NMR, and UV-Vis spectroscopy to better understand the structure and reactivity of the molecules we make.