N-芳基-N-异丙基-2-羟基乙酰胺的合成

Synthesis of N-Aryl-N-isopropyl-2-hydroxyacetamide

以 4个不同结构的芳胺为原料 ,经过N 烷基化 ,N 氯乙酰化 ,酯化 ,酯交换反应合成了 4个 2 羟基乙酰胺类化合物 ,它们都是重要的农药中间体。其中N (4 三氟甲基苯基 ) N 异丙基 2 羟基乙酰胺的合成 :控制温度在 10～ 2 0℃ ,向 4 三氟甲基苯胺 ,冰醋酸与丙酮的混合液中慢慢加入硼氢化钾 ,加完后 2 0℃反应 2h得到产品N 异丙基 4 三氟甲基苯胺 ,产率 86 .0 %。升温至40℃ ,向N 异丙基 4 三氟甲基苯胺、甲苯混合液中滴加氯乙酰氯 ,滴完后升温至 75℃ ,通氮气反应 2h得到产品N (4 三氟甲基苯基 ) N 异丙基 2 氯乙酰胺 ,产率 92 .9%。N (4 三氟甲基苯基 ) N 异丙基 2 氯乙酰胺 ,甲醇 ,醋酸钾 ,三乙胺 ,碳酸钾 ,回流反应 17h ,得到产品N (4 三氟甲基苯基 ) N 异丙基 2 羟基乙酰胺 ,产率 88.2 % ,总收率为 70 .5 %。

N-Aryl-N-isopropyl-2-hydroxyacetamides are a series of important intermediates of useful pesticides. Four N-aryl-N-isopropyl-2-hydroxyacetamides were prepared from four arylamines with different structure through N-alkylation, N-chloroacetylation, esterification and transesterification. Thus, keeping temperature at 10-20°C, potassium borohydride was added in parts to the solution of 4-trifluoromethylaniline and acetone in glacial acetic acid. It was then stirred at 20°C for two hours to get N-isopropyl-4-trifluoromethylaniline, in 86% yield. Chloroacetyl chloride was added dropwise at 40°C to the solution of N-isopropyl-4-trifluoromethylaniline in toluene and the temperature was raised to 75°C. The reaction lasted for two hours at this temperature with nitrogen bubbling through the solution. N-(4-Trifluoromethylphenyl)- N-isopropyl-2-chloroacetamide was obtained in 92.9% yield. N-(4-Trifluoromethylphenyl)-N-isopropyl-2-hydroxyacetamide was obtained by refluxing the mixture of N-(4-trifluoromethylphenyl)-N-isopropyl-2-chroloroacetamide, methanol, triethylamide, potassium acetate and potassium carbonate in 88.2% yield. The overall yield was 70.5%. The product was identified by 1HNMR and CIMS.