新型防腐剂富马酸乙二醇甲酯催化合成条件的优化

Optimization of Catalytic Synthesis Conditions of the New Type Preservative of Glycol Methyl Fumarate

采用一锅法合成了具有α,β-不饱和羰基结构的新型防腐剂富马酸乙二醇甲酯.以马来酸酐、乙二醇和甲醇为原料,对甲苯磺酸为醇解催化剂,硫酸氢钠为酯化催化剂,无水三氯化铝为异构化试剂,用单因素实验法和正交试验法探究了马来酸酐与乙二醇物质的量比、马来酸酐与甲醇物质的量比、醇解反应温度和反应时间对产率的影响.实验结果表明,马来酸酐与乙二醇物质的量比为1:0.8、马来酸酐与甲醇物质的量比为1:2.5,醇解反应温度为140℃,反应时间为3 h,富马酸乙二醇甲酯总产率最高可达59.6%,平均单程产率为85.2%.

The new preservative glycol methyl fumarate containing α,β-unsaturated carbonyl group was synthesized by one-pot reaction. It was synthesized by compounding maleic anhydride, glycol and methanol with p-methyl benzene sulfonic acid as alcoholysis catalyst, sodium hydrogen sulfate as esterification catalyst and anhydrous aluminum chloride as isomerization agent. The molar ratio of maleic anhydride and glycol, maleic anhydride and methanol, the alcoholysis reaction temperature and time were explored by single factor experiments and orthogonal experiments. The results show that the molar ratio of maleic anhydride and glycol was 1: 0.8, the molar ratio of maleic anhydride and methanol was 1: 2.5, the alcoholysis reaction temperature was 140 ℃, and alcoholysis reaction time was 3 hours, the glycol methyl fumarate yield was up to 59.6%, and the average of single step yield was 85.2%.