Dr. Elisabeth Bell-Loncella, Department of Chemistry, University of Pittsburgh, Johnstown, is supported by the Inorganic, Bioinorganic, and Organometallic Program of the Chemistry Division under a Research Planning Grant to study nitrogenase model systems. The role of the driving force of the redox-active metal and the number of acid-labile protons on the non-innocent ligand are the focus of this proposal. Planning activities involve the synthesis and characterization of a series of oxime complexes coupled to bis(bipyridyl)ruthenium. The goal is to determine the conditions which facilitate proton-coupled electron transfer over a range of oxidation states. The project is intended to lay the foundation for further study of the synergistic transfer of protons and electrons, and will be included as preliminary data in preparation of a Faculty Research Project Proposal to be submitted through the NSF's Research at Undergraduate Institutions program. Nitrogenase is an important enzyme in plants which allows for the conversion of molecular nitrogen to ammonia, an essential plant nutrient. The mechanism of this conversion involves the simultaneous transfer of protons and electrons, and metals such as ruthenium play a key role in facilitating these transfer processes. Ruthenium complexes will be synthesized and studied as models for this fundamental biological process, and the factors affecting the transfer processes will be determined.
