The 2-acetamido-4-[hydroxy(methyl)phosphonyl]but-2-enoic acid,an intermediate for producing glufosinate-ammonium,was synthesized with diethyl acetamidomalonate as a start material through hydrolysis and condensation reactions. The yield of monoethyl ester was 85.3％ by hydrolysis with 1.02:1 mole ratio of sodium hydroxide to diethylacetamidomalonate at 25 ℃-30 ℃ for 16 h. The yield of main products after condensation reached 74％ with 1.1/1/10/(3-4)mole ratio of monoethyl ester/ phosphonic aldehyde/ pyridine/anhydride. Finally,the structures of the product,2-acetamido-4-[hydroxy(methyl)phosphonyl]but-2-enoic acid was characterized by 1H, 13C and 31P nuclear magnetic resonance spectroscopy. Its total yield of intermediate is 63.1％ under the optimum reaction conditions. This synthetic route is suitable in industry production with simple operation and mild conditions.%设计并合成了一种草铵膦的新型中间体2-乙酰氨基-4-[羟基(甲基)膦酰基]丁-2-烯酸.以乙酰氨基丙二酸二乙酯为初始原料,经水解,缩合反应得到终产物.该路线的反应条件如下:水解反应时,NaOH和原料摩尔比为1.02:1,反应温度25℃～30℃,最佳反应时间16 h,中间物单乙酯的收率85.3％;缩合反应时,最佳投料摩尔比为n(单乙酯):n(膦醛):n(吡啶):n(乙酸酐)=1.1:1:10:(3～4)时,缩合产物收率74％.最后对产物2-乙酰氨基-4-[羟基(甲基)膦酰基]丁-2-烯酸经1H NMR,13C NMR,31P NMR进行了表征.通过优化反应条件,总收率达到63.1％,该路线工艺简单,条件温和,适合工业生产.
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