9412964 Jenks Iowa State University The photochemistry and photophysics of aromatic sulfoxides will be studied. Three specific objectives will be pursued: (1) Elucidation of the photophysics of aromatic sulfoxides, including the nature of the excited states and mechanisms of intermolecular quenching, (2) A detailed study of the following photochemical reactions and primary mechanistic steps: stereochemical inversion at sulfur, a-cleavage, hydrogen atom abstraction, deoxygenation, and addition to olefins, (3) The design of classes of useful transformations based on mechanistic understanding of the reaction. The experimental studies will be coupled with molecular orbital calculations. This grant from the Organic Dynamics Program supports the work of Professor William S. Jenks at Iowa State University. Photochemistry and Photophysics of a class of organic compounds will be studied. These compounds are characterized by having sulfur bonded to one oxygen atom and to a benzene-type group. The latter group is sometimes referred to as aromatic, and consists of six-carbon atoms bonded in a ring. The individual steps by which these compounds undergo reaction upon radiation with ultraviolet light will be investigated in detail. These studies will form the basis for the design of useful synthetic routes to complex organic molecules.