一锅法合成2-硫脲嘧啶

Synthesis of 2-Thiouracil by One-pot Method

采用一锅法合成了2-硫脲嘧啶,最佳反应条件为:硫脲33 mmol,n(乙酸乙酯)∶n(甲酸乙酯)∶n(甲醇钠)∶n(硫脲)=2.5∶2.0∶1.5∶1.0;乙酸乙酯与甲醇钠在甲苯(35 mL)中于80℃反应3 h;冷却后滴加甲酸乙酯,于25℃充分搅拌8 h后加入硫脲的乙醇(10 mL)溶液,回流反应3 h,收率54.7%。

2-Thiouracil was synthesized by one-pot method. The yield could reach 54.7% under the optimum reaction conditions. Thiourea was 33 mmol. n （ethyl acetate） ： n （sodium methoxide） ： n （ ethyl formate） ： n（thiourea） was 2.5 ： 2.0 ： 1.5 ： 1.0. Ethyl acetate reacted with sodium methoxide in 35 mL toluene at 80 ℃ for 3 h, then ethyl formate was added dropwise at 25 ℃, and thiourea in 10 mL alcohol was added after stirring at 25 ℃ for 8 h, followed by refluxing for 3 h.