Organophosphorus compounds. VI. The 'abnormal' Michaelis-Becker reaction. Diethyl 1-phenylepoxyethylphosphonate and diethyl 1-phenylvinylphosphate from diethyl phosphonate and phenacyl chloride

Abstract

Phenacyl chloride reacts with sodium diethyl phosphonate in liquid ammonia solution to yield a 7 : 3 mixture of diethyl 1-phenylepoxyethylphosphonate (Ia) and the isomeric diethyl 1-phenylvinyl phosphate (IIa). Reaction of phenacyl chloride with diethyl phosphonate and triethylamine in benzene gives only diethyl 1-phenylvinyl phosphate. The action of hydrogen chloride on the epoxide (Ia) gives diethyl 2-chloro-1-hydroxy-1-phenylethylphosphonate (IV). This chlorohydrin reacts with sodium amide in liquid ammonia or with sodium hydroxide in ethanol to again yield a mixture of (Ia) end (IIa); with triethylamine in benzene, the product is mainly the vinyl phosphate (IIa).