一锅法合成4-甲基-5-咪唑甲酸乙酯工艺

[目的]寻找一条合成4-甲基-5-咪唑甲酸乙酯的新工艺路线。[方法]以乙酰乙酸乙酯、磺酰氯与甲酰胺为原料,采用一锅法合成一种用途广泛的多功能单体4-甲基-5-咪唑甲酸乙酯。[结果]通过实验,确定了一条合成4-甲基-5-咪唑甲酸乙酯的新工艺:以二氧六环为溶剂,环化时反应温度为120℃,反应时间为4 h,n(乙酰乙酸乙酯)∶n(磺酰氯)∶n(甲酰胺)为1∶1∶2,在该条件下,4-甲基-5-咪唑甲酸乙酯的产率为70%。[结论]该方法路线简单,原料易得,适合工业化生产。

The Preparation of 4-Methyl-5-imidazole-carboxylic Acid Ethyl Ester by One-pot Reaction

[Aims] The aim is to look for a new preparation method of 4-methyl-5-imidazole-carboxylic acid ethyl ester.[Methods] 4-methyl-5-imidazole-carboxylic acid ethyl ester with versatility was prepared from 3-oxo-butyric acid ethyl ester,sulfuryl chloride and formamide by one-pot reaction.[Results] The effect on yield of the mole ratio of materials,reaction temperature,different solvent were discussed by experiments.We could receive the optimal reaction condition,the mole ratio of 3-oxo-butyric acid ethyl ester,sulfuryl chloride and formamide is 1∶1∶2(in mo1),the reaction temperature is 120 °C,the solvent is dioxane.And the syntheses yield of 4-methyl-5-imidazole-carboxylic acid ethyl ester is 70% under this condition.[Conclusions] The new route is simple and the raw materials are easily obtained,which is suitable for industrial production.