Production of cyclic five-membered ring unsaturated phosphine dichlorides

Abstract

In the production of isomeric five-membered ring cyclic unsaturated phosphine dichlorides by reacting an organophosphorus dichloride with a diene, the improvement which comprises carrying out the reaction in a carboxylic acid chloride. The product, without isolation, can be directly used in reaction with the carboxylic acid anhydride corresponding to the acid chloride to produce the phosphine oxide, the reaction producing additional acid chloride from the anhydride.

Dependencies are inferred from the claim text.