A series of dimeric platinum complexes containing bridging (diphenylphosphino)cyclopentadienyl (dppc) ligands will be prepared and characterized by NMR spectroscopy and X-ray diffraction. Dinuclear reductive elimination reactions will result in carbon-carbon bond formation, and the mechanism(s) of these processes will be investigated using isotopic labeling and variable temperature NMR techniques. The dppc-bridged platinum system will be developed in two ways. The first will be to introduce one or more methyl groups onto the cyclopenta- dienyl ring. This will enhance the coordinating ability of the ligand and prevent reversible dissociation of the cyclopenta- dienyl ring, which appears to be a feature of the dinuclear eliminations. Secondly, a bis(phosphino)cyclopentadienyl ligand will be prepared and used to construct homo- and hetero- metallic trimeric and oligomeric complexes. Where two different metals are present in a single complex, chemistry different from that found for either metal alone is expected. %%% In this project in the Inorganic, Bioinorganic, and Organo- metallic Program of the Chemistry Division, Dr. Gordon K. Anderson of the University of Missouri at Saint Louis will prepare dimeric platinum complexes for use as catalysts in carbon-carbon bond forming reactions. This type of reaction is involved in reforming processes and the production of fuels based on ethylene, methanol, or synthesis gas. In addition, complexes containing many metal atoms of different elements will be synthesized for the same purpose.
