Photochemistry of Alkyl Ketones in the Adsorbed State: Effects of Solid Surfaces Upon the Photolysis

Abstract

This chapter discusses the characteristics of the photolyses of alkyl ketones adsorbed on porous Vycor glass that arises from the electronic perturbation and the steric hindrance effects of the surfaces upon the primary and secondary photochemical processes. The effects of surface hydroxyl groups upon the primary and secondary photochemical processes are also discussed, because surface hydroxyl groups have been found to play a significant role in the photochemistry of the adsorbed alkyl ketones. Finally, the effect of surface modification of porous Vycor glass achieved by supporting a small amount of Ni 2+ ions, upon the photolyses is dealt with. These investigations are very important not only to understand what roles the solid surfaces play in the phenomena of the adsorbed molecules both in their excited and ground states, but also to predict the useful photochemical reaction systems on solid surfaces. Studies of the photolyses of alkyl ketones adsorbed on Vycor glass by hydrogen bonding have demonstrated that the photochemical reactions in the adsorbed layer indicate some deviations in the reaction yields and selectivity as compared with those in the gas phase.