This project in the Inorganic, Bioinorganic and Organometallic Chemistry Program is concerned with metal phosphorus compounds with layered structures containing cavities which may be exploited for catalysis or in chemical separations. These compounds are related structurally to the zeolites which are used extensively in water purification and as industrial catalysts or catalyst supports. A variety of metal organophosphates and phosphonates with layered structures will be synthesized and characterized. Metals will be chosen with valences ranging from 2+ to 4+, and mixed valence compounds will be prepared also. Functionalized derivatives in which the pendant organic groups contain amino, carboxlylic or sulfonic acid groups, or with polyether or polyamine chains as pendant groups, will be prepared. Bridging by polyether or polyamine chains is expected to yield cryptand-like structures, whereas bridging by biphenyls is expected to yield thermally stable structures. The organophosphonates will be decomposed thermally in an attempt to produce novel inorganic layered phosphates, and will be subjected to controlled hydrolysis to prepare new layered hydroxides and oxides. Applications of the new materials in catalysis, ion exchange and specific sorption will be examined. For example, the role of Lewis acid versus Bronsted acid sites in acid catalyzed reactions will be assessed.
