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Inventing chemical reactions for new syn-theses using organometallic complexes and the design of new biodegradable polymers

based on polylactic acids is the focus of our research. In addition to basic training in synthesis and polymer chemistry, students in my group develop expertise in the gamut of modern analytical methods for molecu-lar and macromolecular characterization and are exposed to a broad range of sci-ence through exten-sive collaborations with other groups on campus. Overviews of two current projects are given below.

The first project involves transition metal chemistry of boron. We began our research in this area with hopes of exploring the fun-damental chemistry of metal boryl complex-es (M–BX2) and examining reactions of bo-ron-element bonds with unsaturated organic ligands coordinated to metal centers. In the course of this work, we discovered unusual selectivities for olefin borylation reactions and were able to control catalytic chemis-try by tuning the ligands attached to boron.

Most recently, we reported the first example of catalytic synthesis of a B–C bond from an arene C–H bond and a borane B–H bond. This marked a significant advance in catalytic hy-drocarbon functionalization, which has been one of chemistry’s “Holy Grails”. In addition, the sterically dictated regioselectivities in

these reactions provide the first general solu-tions to long-standing problems in aromatic substitution chemistry. In the future, we plan to explore issues that dictate selectivity in these reactions.

The second research area involves the synthe-sis of biodegradable and biorenewable poly-mers through ring-opening polymerization

reactions. These are important materials that provide environmentally friendly alternatives to petroleum-based polymers. We present-ly are designing polylactic acid copolymers that can be tailored for applications in tissue regeneration and drug delivery. This project has spawned a collaboration studying bone growth with the Department of Physiology.

Bone forming cells (osteoblasts) grown on a “tailored” PLA copolymer.

Professor (b. 1964)

B.S., 1986, California Institute of Technology;

Ph.D., 1990, Univ. of Chicago;

Postdoctoral Fellow, 1990-92, Univ. of California, Berkeley.

517-355-9715, Ext. 166

Organometallic Chemistry and Polymer Interactions within Biological Systems

Milton R. (Mitch) Smith

C–H Activation/Borylation/Oxidation: A One-Pot Unified Route to Meta-Substituted Phelols Bearing Ortho-/Para-Directing Groups, R. E. Maleczka Jr., F. Shi, D. Holmes, M.R. Smith III, J. Am. Chem. Soc. 2003, 125, 7792.

Remarkably Selective Iridium Catalysts for Elaboration of C–H Bonds, J.-Y. Cho, M. K. Tse, D. Holmes, R. E. Maleczka Jr., M. R. Smith III, Science 2002, 295, 305.

Steric and Chelate Directing Effects in Aromatic Borylation, J.-Y. Cho, C. N. Iverson, M. R. Smith III, J. Am. Chem. Soc. 2001, 123, 12868.

Stereoselective Polymerization of a Racemic Monomer with a Racemic Catalyst: Direct Preparation of the Polylactic Acid Stereocomplex from Racemic Lactide, C. P. Radano, G. L. Baker, M. R. Smith III, J. Am. Chem. Soc. 2000, 122, 1552.

Stoichiometric and Catalytic B–C Bond Formation from Unactivated Hydrocarbons and Boranes, C. N. Iverson, M. R. Smith III, J. Am. Chem. Soc. 1999, 121, 7696.

Selected PublicationS