2-乙酰基-3-甲基-5-(N-甲苯氨基)噻唑的合成

N 甲基苯胺与盐酸及硫氰酸钾回流反应5h,然后用水重结晶得到了N 甲基 N 苯基硫脲,产率40%。将2,4 戊二酮分散到四氯化碳-水的混合溶液中,然后将溴的四氯化碳溶液在1h内滴加到上述溶液中,控制温度为0℃,搅拌45min后,分离出四氯化碳层并蒸去四氯化碳,得到油状物,即为3 溴 2,4 戊二酮,产率79%。3 溴 2,4 戊二酮及N 甲基 N 苯基硫脲溶于丙酮中,回流30min,冷却,然后用碳酸钠溶液碱化,再用乙酸乙酯萃取,蒸去乙酸乙酯就得到2 乙酰基 3 甲基 5 (N 甲苯氨基)噻唑,产率62%。

Synthesis of 2-Acetyl-3-methyl-5-(N-methylanilino)thiazole

N Methylaniline was refluxed with aqueous HCl and KSCN for 5 h and then recrystallized in water to give N methyl N phenylthiourea(Ⅰ) in 40% yield.A solution of Br2 in CCl4 was added during 1 h to a stirred dispersion of 2,4 pentanedione in CCl4-H2O at 0 ℃.After stirring for 45 min,the CCl4 layer was separated,and evaporated to give oily 3 bromo 2,4 pentanedione (Ⅱ) in 79% yield.A solution of Ⅰ and Ⅱ in acetone was refluxed for 30 min,cooled,basified with Na2CO3 solution,and extracted with ethyl acetate.After evaporation to remove ethyl acetate,2 acetyl 3 methyl 5 (N methylanilino)thiazole was obtained in 62% yield.