SO_4^(2-)/ZrO_2型固体超强酸催化合成乙基香兰素1,2-丙二醇缩醛

Synthesis of Ethyl Vanillin 1,2-Propylene Glycol Acetal Catalyzed by SO_4^(2-)/ZrO_2 Solid Superacid

以乙基香兰素和丙二醇为原料,SO42-/ZrO2型固体超强酸为催化剂,合成了乙基香兰素1,2-丙二醇缩醛,考察了带水剂种类、催化剂用量、反应时间、原料摩尔比等对产率的影响.实验表明较优的反应条件为:乙基香兰素用量0.05 mol,n(乙基香兰素)∶n(1,2-丙二醇)=1∶1.5,固体超强酸用量为乙基香兰素质量的1.2%,带水剂为甲苯20 mL,回流反应9.0 h.在此条件下,乙基香兰素1,2-丙二醇缩醛收率为96.6%.并通过红外光谱、1H NMR、13C NMR、气质联用对所合成的目标产物结构进行了表征.

The synthesis of ethyl vanillin 1,2-propylene glycol acetal was studied. Factors influencing the yield, such as different water-entraining agents, catalyst amounts, reaction time, molar ratio of materials et al, were discussed and the better reaction conditions were determined. The optimum conditions are as follows： ethyl vanillin is 0.05 mol, n（ ethyl vanillin） ： n（ 1, 2-propylene glycol） = l： 1.5 ; the water-entraining agent is toluene （20 mL） ; the amount of catalyst is 1.2% of the weight of ethyl vanillin ; the reaction time is 9. 0 h. Under these conditions, the yield of ethyl vanillin propylene glycol acetal is 96. 6%. The structure of was identified by means of IR, 1H NMR, 13C NMR and GC-MS. Key words：ethyl vanillin 1,2-propylene glycol acetal, ethyl vanillin, propylene glycol, SO2-/ZrO2 solid superacid