PROCESS FOR THE PREPARATION OF VINYLPHOSPHONIC DICHLORIDE

摘要

HOE 86/F 224 The invention relates to a process for the preparation of vinylphosphonic dichloride, in which a 2-chloroethane-phosphonate of the formula or or a mixture of the two esters, is reacted with thionyl chloride at a temperature of 60 to 160.degree.C in the presence of a catalyst which contains tertiary phosphines, quaternary ammonium or phosphonium salts or alkali metal or alkalineearth metal halides. During this reaction, any thionyl chloride which may be present is removed by distillation subsequent to this reaction, the mixture remaining is heated to 140 to 200.degree.C, and the vinylphosphonic dichloride produced during this is removed by distillation.