乙酰氨基丙二酸二乙酯合成新工艺研究

Study on the Synthesis of Diethyl Acetamidomalonate

以丙二酸二乙酯、冰醋酸、亚硝酸钠为原料 ,n( CH2 - ( COOC2 H5) 2 )∶ n( CH3 COOH)∶n( Na NO2 ) =1∶ 2∶ 2 ,加入相转移催化剂合成肟基丙二酸二乙酯 ( DEOM) ,节省冰醋酸和亚硝酸钠的使用量。 DEOM用 CH2 Cl2 萃取 ,然后将 DEOM在 40～ 5 0℃、醋酸介质中加锌粉还原 ,乙酐酰化 ,用水结晶得产品乙酰氨基丙二酸二乙酯 ( DEAM) ,熔点 96.5～ 97.5℃ ,相对于丙二酸二乙酯收率为 79.6%。

Diethyl oximinomalonate(DEOM) was prepared from diethyl malonate, glacial acetic acid and sodium nitrite with n (CH 2(COOC 2H 5) 2)∶ n HAC∶ n (NaNO 2)=1∶2∶2 in the presence of phase transfer catalyst so as to save HAc and NaNO 2. DEOM was extracted with CH 2Cl 2. Diethyl acetamidomalonate was obtained by reducing DEOM with Zn powder and acylating with (Ac) 2O in HAc medium at 40～50℃. The product was crystallized in water. The yield of the title compound was 79.6% , and its mp. was 96.5 ～ 97.5 ℃.