Development of a Colloidal Redox System Containing a Smectite Clay for Control ofReactivity and Reaction Selectivity

摘要

This project is directed towards the development of colloidal redox systemsinvolving smectite clays:. Two polypyridylosmium(II) complexes containing ligands bearing anionic pendant groups have been synthesized. Each complex has been successfully incorporated into stable montmorillonite colloids. Approximately 96 - 99% of the complex adsorbs onto the colloidal montmorillonite for loadings up to 1 mmole/g. These findings demonstrate the utility of adding a negatively charged side group to a complex to prevent simultaneous adsorption of the complex on two clay particles, which produces flocculation. Electrochemical studies of these colloidal redox systems indicate that at least part of the clay-adsorbed complex is accessible for electron transfer. These properties are prerequisites for the development of new catalytic systems based upon the incorporation of transition-metal catalysts into clay colloids. In order to develop such a system, two bipolar aquaruthenium(II) catalysts have been synthesized. These aquaruthenium(II) catalysts can also be incorporated into stable montmorillonite colloids. Characterization of clay colloids containing these catalysts is in progress. Montmorillonite, Clay Colloids, Osmium Complexes, Electrochemistry, Aquaruthenium(II) Complexes.