申请人:Crompton & Knowles Corporation
公开号:US04830788A1
公开(公告)日:1989-05-16
A process is disclosed for the preparation of N-substituted aminomethylphosphonic acids, particularly methylaminomethylphosphonic acid, in high yield and purity with related low production cost using conventional equipment, which comprises the steps of (a) reacting an N-substituted amide with paraformaldehyde in a low molecular weight carboxylic acid to form the N-methylol derivative, (b) reacting the N-methylolamide with PCl.sub.3 i n excess low molecular weight carboxylic acid and heating to form the phosphonomethyl derivative, (c) hydrolyzing acid chloride and acid anhydride with water, (d) distilling off the low-molecular weight carboxylic acid, (e) hydrolyzing the N-acyl group with water and strong acid catalyst, (f) adding low molecular weight alcohol to crystallize the N-substituted-aminomethylphosphonic acid and (g) filtering, and washing the product.
揭示了一种制备N-取代氨甲基膦酸的过程,特别是高产率和纯度的甲基氨甲基膦酸,使用常规设备相关低生产成本,包括以下步骤:(a) 在低分子量羧酸中将N-取代酰胺与多聚甲醛反应,形成N-甲基醇衍生物,(b) 将N-甲基醇酰胺与过量的低分子量羧酸中的PCl.sub.3 反应并加热,形成磷膦甲基衍生物,(c) 用水水解酸氯和酸酐,(d) 蒸馏掉低分子量羧酸,(e) 用水和强酸催化剂水解N-酰基团,(f) 添加低分子量醇结晶化N-取代氨甲基膦酸,(g) 过滤并洗涤产物。