Process for the preparation of 2-chloroethanephosphonic dichloride

摘要

The invention relates to a process for the preparation of 2-chloroethanephosphonic dichloride through reaction of a 2-chloroethanephosphonate of the formula <IMAGE> +TR <IMAGE> or a mixture of the two esters, with thionyl chloride at a temperature of 60 DEG to 160 DEG C. In this reaction, tertiary phosphines, quaternary ammonium or phosphonium salts or alkali metal or alkaline-earth metal halides are employed as catalysts. The thionyl chloride is introduced into the initially introduced ester.