一锅法合成4-溴丁基乙酸酯

One-pot synthesis of 4-bromobutyl acetate

以1,4-丁二醇、氢溴酸(48%)和冰醋酸为原料,在带水剂的作用下一锅法合成了4-溴丁基乙酸酯。考察了带水剂类型及追加冰醋酸或醋酸酐量对产率的影响,并通过气质联用对粗产品进行了分析测定,推断其反应机理。结果表明,较适宜的合成条件为1,4-丁二醇0.21 mol,1,4-丁二醇∶氢溴酸(48%)∶醋酸摩尔比为1∶1∶1.3,在带水剂甲苯(21 mL)的作用下,反应2.5 h,反应结束前1 h追加0.01 mol醋酸酐,合成效果最好,产率可达到91.2%,反应主要副产1,4-二溴丁烷、4-溴-1-丁醇、四氢呋喃和1,4-丁二醇二乙酸酯。

4-Bromobutyl acetate was synthesized by reacting 1,4-butanediol with an aqueous solution of hydrogen bromide（48% ） and acetic acid（ 1 ： 1 ： 1.3） in the water-carrying agent. The effect of the type of water-carrying agent and the additional quantity of acetic acid or acetic anhydride on the yield was investigated, meanwhile, the crude product was analyzed by GC-MS and the reaction mechanism was deduced. The experimental result shows that the optimal condition was as follows ：the molar ratio of 1,4-butanediol,hydrogen bromide,and acetic acid was 1 ： 1 ： 1.3 when 1,4-butanediol was 0.21 mol,refluxed 2.5 h under the action of 21 mL toluene. After reacting 1 h,added additional 0.01 mol acetic anhydride, the yield was high up to 91.2% with the main by-products of 1,4-dibromobutane ,4-bromo-1-butanol, tetrahydrofuran and 1,4-diacetoxybutane.