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Research Synopsis:
Inorganic, Organometallic, and Green听Chemistry:

Synthesis, characterization, and reactivity of molecules and materials with catalytic applications; organoaluminum听catalysts and cocatalysts; Lewis acids, alkylaluminoxane analogues; epoxide polymerization catalysts; hydroformylation; biomass conversions.

My group is currently pursuing听four areas of research: (1)听Design of听aluminum complexes for use in catalysis and听for the activation of small molecules, (2) development of early transition metal complexes for the oligomerization and polymerization of alkenes, (3) development of new phosphorus ligands for applications in hydroformylation of alkenes and C-C coupling reactions in ionic liquids, and (4) the conversion of biomass to chemicals and polymers.听

The interest in aluminum chemistry is driven by the high natural abundance and low cost of aluminum (), the high reactivity of organoaluminum reagents with small molecules, and the similarities of aluminum(III) chemistry to that for some of the early transition metals.听听Our research focusses on developing new ways to activate small molecules such as CO, the development of Lewis acid catalysts and cocatalysts for the polymerization of epoxides and cyclic lactones, and the polymerization and oligomerization of alkenes.听 This chemistry occasionally extends to other group 13 elements, mainly boron and gallium.听 In recent years we have made extensive use of ligands that incorporate indole and pyrrole moieties.听 Molecular structures of some recent examples are shown below.

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Our work on the functionalization,听oligomerization and polymerization of alkenes with early transition metal complexes听focusses on听development of听unique indole- and pyrrole-based ligands.听 Although the polymerization and oligomerization of alkenes by early transition metal complexes听has been听heavily investigated in industry and academia, our ligands systems are unique.听 One family of ligands currently under investigation is comprised of cyclopentadienyl moiety tethered to a diindolylethane or dipyrroethane.听 Upon deprotonation, these ligands are trianionic and provide a unique coordination environment around the metal as shown in the ORTEP below.听 We are currently exploring the coordination chemistry and reactivity of this family of ligands.听听听

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The conversion of biomass to chemical products is a new project for the group, and is听being conducted in collaboration with Professor Sas Varanasi, Department of Chemical and Environmental Engineering, and an industrial sponsor.听 This work is supported by an SBIR grant from the Department of Energy.

Additional research interests include the synthesis of novel phosphorus ligands with applications in homogeneous catalysis, including hydroformylation of alkenes and C-C coupling reactions in ionic liquids.

Consistent with our breadth of research interests, my group utilizes a broad range of synthetic and characterization techniques, including the handling of air- and moisture sensitive reagents, solvothermal synthesis, solution and solid-state multinuclear NMR spectroscopy, infrared spectroscopy, and X-ray crystallography.听 We also utilize isothermal titration calorimetry in collaboration with Professor Bob Flowers at Lehigh University.听

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