Method for preparing 4-(hydroxymethylphosphinyl)-2-oxobutanoic acid

Abstract

Provided is a method for preparing 4-(hydroxymethylphosphinyl)-2-oxobutanoic acid, comprising the following steps: a) mixing methylphosphonite diester, carboxylic acid and acryloyl cyanide, performing addition reaction, and performing distillation under reduced pressure to obtain a material solution of (3-cyano-3-carbonylpropyl)methylphosphonate; b) mixing the material solution of (3-cyano-3-carbonylpropyl)methylphosphonate obtained in step a) with water uniformity, cooling to 10° C.-40° C., then adding hydrochloric acid dropwise for acidification, and after the dropwise addition being completed, continuing stirring for 0.1 h-1 h, then performing hydrolysis reaction, and finally performing purification treatment to obtain 4-(hydroxymethylphosphinyl)-2-oxobutanoic acid. In the provided preparation method, cyanation reaction is not required, which avoids the use of cyclic phosphonic anhydride that is high in cost and difficult to obtain and the highly toxic sodium cyanide. In addition, the preparation method has short process steps, wide source of raw materials and low cost, mild reaction conditions, and high comprehensive utilization rate of elements.