Investigation of Radical Cage Effects in Organometallic Chemistry

University Of Oregon Eugene, Eugene OR

Investigators

Abstract

This award by the Inorganic, Bioinorganic, and Organometallic Chemistry Program supports Professor David Tyler at the University of Oregon to investigate the fundamental, underlying principles of radical cage effects with the overall goal of better understanding radical reactivity. The research will focus on four aspects of cage effects. In one study, the still-confusing role of the solvent will be explored using a new model based on the microviscosity of the solvent. Another study will focus on what effect the wavelength of light has on the cage effect in photogenerated radical cage pairs. Preliminary results show a trend opposite to that predicted by theory, and a new principle of dynamics may be uncovered in these experiments. A third investigation will seek confirmation for the existence of secondary (solvent separated) cage pairs. Secondary cage pairs have been hypothesized to explain the effect of radical rotation on radical-radical recombination reactions but secondary cage pairs have not been unequivocally identified. Finally, as part of a study to explore how solvents specifically interact with solute molecules, a fourth study will explore how H-bonding to an H2 ligand in a metal-H2 complex can affect the reactivity of the H2 ligand. The results of these four investigations will give researchers an in-depth understanding of cage effects and how they impact radical reactivity. Although the studies involve organometallic radicals, the fundamental principles uncovered will apply to radicals of all types, whether organic, inorganic, or biochemical. Graduate students involved with this project participate in internship programs. These innovative programs prepare Ph.D. students for successful careers in industry or in academics by placing them in regional companies or in colleges for a one-term internship experience. Companies and colleges are enthusiastic about the program because they have the opportunity to work with interns who have an up-to-date knowledge of chemistry, instrumentation, laboratory techniques, computer skills, and the scientific literature. The research program also fosters closer collaborative ties with local companies and colleges. This has led to professors at regional colleges taking sabbatical leaves in Professor Tyler's lab and to outside students using the instrumentation in the University of Oregon Chemistry Department. Underrepresented groups will have a strong presence in the graduate and undergraduate student audience that participates in the research.