The Brookhart group carries out research in the general area of synthetic and mechanistic organometallic chemistry with particular emphasis on the application of organometallic complexes in catalysis. One major thrust is the development of late transition metal complexes (Ni, Pd, Fe, Co) for olefin polymerization. These non-traditional catalysts allow synthesis of polymers with unique microstructures, such as hyperbranched polyethylene and chain-straightened poly(a-olefins). The functional group tolerance of these late transition metal systems allows copolymerization of monomers such as methyl acrylate with nonpolar monomers such as ethylene and propylene. In addition, new catalysts are also under investigation for living polymerization systems, as well as the alternating copolymerization of olefins and CO to yield polyketones. Mechanistic probes of these reactions employ primarily low temperature IR and NMR spectroscopies and provide a detailed understanding of catalyst resting states and relative intermediates.

A second major focus concerns fundamental studies of C-H and C-C bond activations by transition metal complexes and the incorporation of these bond activation steps into catalytic cycles. Co, Rh, and Ru complexes have been developed which catalyze the ortho-alkylation of aromatic ketones, alkyl aldehyde isomerization, hydroacylation, and the dehydrogenation of alkoxy silanes to generate silyl enol ethers. Again, thorough mechanistic studies dictate the development of second generation catalyst systems.