Tuesday, May 20, 2008 - 4:20 PM
Library Building, Rm LB-15 (Queensborough Community College)
480

From Molecular to Supramolecular to Superdupermolecular Organic Photochemistry

Nicholas Turro, Columbia University, New York, NY

The reactions of carbon centered radical pairs often involves diffusion controlled combination and/or disproportionation reactions which are non-selective. A geminate triplet geminate pair of radicals is produced by the photolysis of suitable ketones. The reactions of such geminate pairs can be controlled though the application of supramolecular concepts which emphasize non-covalent interaction to "steer" the geminate pair toward a selected pathway. In addition, "superdupermolecular" concepts, which emphasize the control of radical pair reactions and spectroscopy through the orientation of electron spins, can be employed to further control the course of geminate pair reactions. Examples of control of a range of the selectivity of geminate radical combinations, which form strong covalent bonds, through supramolecular and superdupermolecular effects will be presented for the photolysis of ketones adsorbed in the supercages of zeolites.