In this project supported by the Inorganic, Bioinorganic and Organometallic Chemistry Program, Louis H. Pignolet of the University of Minnesota will investigate the synthesis, reactivity and characterization of mixed transition metal-gold and silver cluster compounds. Bimetallic alloys of these metals are known to be important commercial catalysts. The reactions of discrete cluster compounds may be useful as models for alloy surfaces and therefore in understanding the fundamental reaction mechanisms at the catalytic metal surfaces. Recent advances in the systematic synthesis of bimetallic clusters will be used as a starting point for the formation of new trimetallic clusters. Emphasis will be placed on gold and silver clusters which also contain platinum or palladium. A preliminary procedure which allows a third unligated metal to add to the external edge of an existing bimetallic cluster will be developed and the resulting complexes will be examined for catalytic activity. In addition, a procedure will be developed for the attachment of the metal cluster compounds to silica and phosphinated polymers, which may have potential use as easily recoverable catalysts.
