Dr. Thomas P. Fehlner, Department of Chemistry, University of Notre Dame, is supported by the Inorganic, Bioinorganic, and Organometallic Program of the Chemistry Division for the synthesis of new clusters containing both main-group and transition-metal atoms. The project is a three pronged investigation. The first part will explore the chemistry of chromaborane and related clusters where electron delocalizion can occur throughout the cluster network. The chemistry of these compounds will be used to define the reactive sites on the clusters, which will then be related to the clusters' electronic structure. Second, efficient synthetic routes, which begin from known monocyclopentadienyl metal complexes, will be developed for dimetallaboranes containing a wide ranging of metals. Thirdly, these dimetallaboranes will be used as ligands to low valent metal fragments in order to form polymetallic species where a transition metal cluster serves as a complex ligand. The chemistry of the transition metals when combined with carbon containing substituents is the basis of the vast field of organometallic chemistry. Research in this area has led to many advances in pure and applied chemistry. This project aims to open a related area in which transition metals are combined with units containing boron. Preliminary results indicate that these `metallaboranes` will possess an extensive chemistry that in some ways resembles organometallic chemistry, but in other ways is very different. In this investigation new combinations of boranes and transition metals will be prepared and their chemistry investigated. The new compounds will express the unique aspects of their electronic structures in new kinds of reaction chemistry.
