Photoreactions of diphosphines with benzophenone
Abstract
Reactions of tetraphenyl- and tetraethyl-diphosphine with photoexcited benzophenone have been studied. In general, the products (after sulphurization with sulphur) are tetraphenylethylene, thiobenzophenone, and phosphinic acids. Diphenylmethyl(diphenyl)phosphine oxide, tetraphenyloxiran, tetraphenylthiiran, and phenyl triphenylmethyl ketone are also formed in amounts depending on the reaction conditions. A mechanism involving metathesis of the P–P bond by n–π* triplet benzophenone is suggested.