The proposed research is in the general area of organometallic chemistry and in the specific area of metal cluster chemistry. The research is expected to provide a clearer understanding of how metal clusters function as catalysts in the synthesis and transformation of organic compounds. The research will focus on two areas of metal cluster chemistry. The first area will address the reaction mechanisms of metal clusters, particularly in homogeneous catalysis. Two approaches will be used to optimize the likelihood that the clusters will remain intact throughout the catalytic cycle. The first will involve the use of halides and pseudohalides to activate simple carbonyl clusters under mild conditions. The second approach will involve the use of mu-3-NR ligands to bind together strongly the metals within the cluster, so that reactions under more vigorous conditions may be studied. The second general area of metal cluster chemistry to be addressed is the synthesis of oligomers and polymers of clusters. Clusters will be linked together with a variety of organic linking groups to provide different types of structures. The redox chemistry of the oligomers will be explored, since unusual electronic properties are expected for the mixed valence species obtained by partial oxidation.
