Photochemistry of Organic Molecules in Microscopic Reactors

ABSTRACT The photochemistry of dibenzyl ketone and its derivatives has been employed to investigate the ability of zeolite molecular sieves to modify and to control the reaction channels available to organic molecules ad-sorbed on the internal and external zeolite surfaces. It is found that the observed photochemistry is very sensitive to the size/shape characteristics of the substrate ketones and of the pores and internal void space of the zeolites. Although unprecedented reactions of ketones have been found to be induced by absorption of the ketones on the zeolite surfaces, the reac-tions are consistent with expectations based on the topological structure of the zeolite surfaces and on the mechanism of ketone photolysis in homo-geneous solution. ZEOLITE MOLECULAR SIEVES. DESIGNER MICROSCOPIC REACTORS Zeolites (fron the Greek words zeo, "to boil " and lithos "stone")1 are synthetic o natural minerals that often expel water so violently when heated that they appear to boil. Classi-cal zeolites are crystalline aluxainosilicates whose internal porous structure contain chan