离子液体催化合成乙二醇丁醚醋酸酯

Synthesis of 2-butoxyethyl acetate in the presence of ionic liquid catalyst

以乙二醇单丁醚和冰醋酸为原料,在离子液体N-甲基吡咯烷酮硫酸氢盐([Hnmp]HSO4)催化下,合成了乙二醇丁醚醋酸酯.考察了催化剂用量、物料配比、反应时间、带水剂等因素对反应收率的影响.利用气相色谱仪分析了产物的纯度;利用核磁共振谱仪和质谱仪表征了产物的结构.结果表明,合成产物的纯度大于99.0%.[Hnmp]HSO4对合成乙二醇丁醚醋酸酯有良好的催化活性;在催化剂用量为反应物料总质量的6%,乙二醇单丁醚用量为11.8g,乙二醇单丁醚与冰醋酸的物质的量之比为1∶2,回流时间为3h,带水剂环己烷用量为15mL的反应条件下,产物收率达94.6%;且催化剂重复使用5次仍保持较高活性.

Ethylene glycol monobutyl ether and acetic acid were used as the starting materials to synthesize 2-butoxyethyl acetate in the presence of ionic liquid 1-methyl-2-pyrrolidinone hydrosulfate as a catalyst.The influence of synthetic conditions such as dosage of catalyst,ratio of acid to alcohol,reaction time and water stripping agent on yield were investigated.The purity of as-synthesized product was determined by gas chromatographic analysis;and its structure was characterized by means of nuclear magnetic resonance spectroscopy and mass spectrometry.Results show that as-synthesized product has a purity of above 99.0%.Ionic liquid 1-methyl-2-pyrrolidinone hydrosulfate exhibits excellent catalytic activity for the synthesis of 2-butoxyethyl acetate.Target product 2-butoxyethyl acetate is obtained at a yield of 94.6% when the dosage of catalyst（vs.total mass of reactants）,amount of ethylene glycol monobutyl ether,molar ratio of ethylene glycol monobutyl ether to acetic acid,refluxing time,and dosage of cyclohexane are kept as 6%,11.8 g,1∶2,3 h,and 15 mL,respectively.Besides,the catalyst can be reused for five times without significant loss in yield.