1-甲基-3-烷基咪唑/AlCl_3催化合成反丁烯二酸二甲酯

SYNTHESIS OF DIMETHYL FUMARATE BY 1-METHYL-3-ALKYLIMDAZOLIUM/AlCl_3CATALYST

研究了顺丁烯酸酐和甲醇在 1 甲基 3 烷基咪唑 /AlCl3 催化作用下 ,经异构化和酯化反应合成反丁烯二酸二甲酯化合物。用统计序贯实验设计方法对合成过程进行了优化。开发了一条产品收率高 ,与盐酸、三氯化钕等催化工艺相比具有无腐蚀、无污染、价廉等优点的制备工艺。实验结果表明 ,1 甲基 3 烷基咪唑 /AlCl3 催化剂具有异构化和酯化两种催化作用 ,省去了以顺丁烯二酸酐为原料先制备富马酸中间产品的过程 ,反应条件温和 ,操作简便 ,一步法即可得到产品 ,其纯度为 99.4 %。最佳工艺条件为 :催化剂用量与顺丁烯二酸酐摩尔比为 0 .17∶1、甲醇与顺丁烯二酸酐摩尔比为 4 .0 1∶1、反应温度为 93.0℃、反应时间为 5 .0小时。在实验条件下 ,反丁烯二酸二甲酯的收率达到 90 %。

In this paper, dimethyl fumarate was synthesized by isomerization and esterificatoin of maleic anhydride and methanol under 1 methyl 3 alkyl imdazolium/AlCl 3 catalysts. The process of one step method was developed and optimized. The reaction temperature, amount of the catalyst, reaction time, material molar ratio and reaction time were optimized by the method of sequential discriminate procedure for design of experiments. Experimental results have indicated that 1 methyl 3 alkyl imdazolium/AlCl 3 can catalyze the isomerization of maleic anhydride and esterification of fumaric acid, and the optimum conditions are: the molar ratio of catalyst to maleic anhydride is 0.17, that of methanol to maleic anhydride 4.01, the reaction temperature 93.0℃,the reaction time 5.0 hours, and the yield of dimethyl fumarate can reach 90%.