Exploratory studies of H-atom abstraction and silyl-transfer photoreactions of silylalkyl ketones and (silylalkyl)phthalimides

Irradiation of silylalkyl ketones and (silylalkyl)phthalimides in less polar-nonsilophilic solvents generates an equal yield of acetophenone and vinyltrimethylsilane through gamma-H atom abstraction and 1,4-biradical fragmentation. But the irradiation of these compounds in polar-silophilic solvents leads to acetophenone and vinyltrimethylsilane in 1.7:1 ratio. The excited state electron transfer reaction between excited carbonyl and ground state sigma(sub C-Si) in silophilic solvents causes C-Si bond scission, and the activation of excited-state reaction paths.