The goal of this project is to establish the feasibility of using flow and stopped-flow NMR spectroscopy to study rapid (less than one second half-life) organometallic reactions. The combination of NMR spectroscopy, the most powerful method for characterizing organometallic species in solution, with rapid mixing techniques may provide a valuable probe of the structures and kinetics of important, previously unobservable intermediates in element-H activation, olefin insertion, and other important organometallic reactions. Three specific systems from ongoing research that will be studied are: 1) E-H activation (E = C, B, H) reactions of dinuclear tantalum complexes, 2) CO and RNC insertion reactions of cyclopentadienyl tantalum complexes, and 3) olefin and acetylene insertion reactions of electrophilic zirconium complexes. The results may yield new mechanistic insights to these specific reactions, and will provide the basis for more general application of these NMR techniques in organometallic chemistry. %%% With this Grant for Exploratory Research from the Inorganic, Bioinorganic, and Organometallic Program of the Chemistry Division, Dr. Louis Messerle and Dr. Richard F. Jordan of the University of Iowa will endeavor to establish the feasibility of using nuclear magnetic resonance (NMR) spectroscopy for the study of rapid organometallic reactions that are complete within a few seconds. This technique should enable the observation of unstable reaction intermediates and shouldsubstantially extend our understanding of the mechanisms of these important reactions.
