With the support of the Organic and Macromolecular Chemistry Program, Professor James M. Tanko, of the Department of Chemistry at Virginia Polytechnic Institute and State University, is studying the principals and applications of radical ion rearrangements. Professor Tanko is exploring the structural features which govern the rate of rearrangement of radical anions derived from carbonyl compounds as well as the influence of solvent and counterion on these rearrangement reactions. Study of the oxidation potentials of cyclopropyl- and cyclobutylamines and determination of rate constants for the ring opening reactions of radical cations generated from their oxidation may shed light on the biological oxidations catalyzed by monoamine oxidase. Both electrochemical and laser flash photolysis methods will be used to generate the desired ions. Information regarding the driving force for ring opening will be obtained from appropriately constructed thermodynamic cycles, while theoretical methods will be used to provide information regarding the structure of radical ions and to estimate thermodynamic properties in situations where such information cannot be obtained experimentally.
Molecules bearing both a net charge (either positive or negative) and an unpaired electron appear as key intermediates in many chemical and biological processes. Development of an understanding of the structure and dynamics of these so-called radical cations and anions is central to elucidation of the fundamental details of how such processes occur. With the support of the Organic and Macromolecular Chemistry Program, Professor James M. Tanko, of the Department of Chemistry at Virginia Polytechnic Institute and State University, is carrying out studies of the preparation, structure, and reaction chemistry of radical anions and radical cations. Through a combination of experimental and theoretical approaches, Professor Tanko is shedding light on the nature of these elusive intermediates, addressing fundamental issues of organic reaction mechanism and leading to a deeper understanding of the function of biological catalysts such as monoamine oxidase.
