In this project in the Inorganic, Bioinorganic and Organo- metallic Chemistry program, Karl M. Kadish of the University of Houston will investigate the electron transfer reactivity and spectroscopic properties of a wide variety of metalloporphyrins. Metallophorphyrins are model compounds for numerous metallo- proteins and enzymes such as hemoglobin, chlorophyll and vitamin B-12 and their study, especially redox behavior and electron transfer mechanisms, is important for understanding the modes of action of these bioinorganic systems. A broad based selection of monometallic, bimetallic and trimetallic metalloporphyrins will be examined by the usual electrochemical methodologies as well as by UV-visible, FTIR and ESR spectroelectrochemistry of the in situ products and/or intermediates produced in each electrode reaction. Stable electrooxidation/reduction products will be isolated and characterized by usual methods. Special emphasis will be placed on metal-carbon and metal-metal bonded metalloporphyrins as well as on metalloporphyrins in high and low oxidation states and those with diatomic molecules as ligands. Water soluble porphyrins will be investigated in aqueous and non-aqueous media as will be porphyrins in micelles.
