二乙二醇甲基丁基醚的合成

以二乙二醇单甲醚(C_5H_(12)O_3)和氢氧化钠为原料、苯为带水剂,在n(NaOH):n(C_5H_(12)O_3)=1．5:1．0和不断通入N_2的条件下,合成了二乙二醇单甲醚钠。通过正溴丁烷与二乙二醇单甲醚钠的Williamson反应合成了二乙二醇甲基丁基醚(DGBME)。研究了醚化反应的温度和时间及正溴丁烷(n-C_4H_9Br)与二乙二醇单甲醚的摩尔比对DGBME收率的影响,用气相色谱法分析了产物含量,并用FT-IR和~1H NMR表征了产物结构。实验结果表明:反应温度80℃,醚化反应时间4．0h,n(正溴丁烷):n(二乙二醇单甲醚)=1．06为适宜的反应条件,在此条件下DGBME的收率为92．14%;气相色谱法分析产物中DGBME含量在99．5%以上。

SYNTHESIS OF DIETHYLENE GLYCOL BUTYL METHYL ETHER

Under the conditions of n(NaOH):n (C_5H_(12)O_3)=1.5:1,benzene as water carrying agent and in the presence of N_2,sodium of diethylene glycol mono-methyl ether was prepared with diethyl- ene glycol mono-methyl ether (C_5H_(12)O_3) and sodium hydroxide as starting materials.Diethylene gly- col butylmethyl ether (DGBME) was synthesized through the Williamson reaction between butyl bro- mide (n-C_4 H_9 Br) and CH_3 OCH_2 CH_2OCH_2 CH_2 ONa.The influences of the reaction temperature,re- action time and mass ratios of n-C_4H_9Br to diethylene glycol mono-methyl ether on the yield of DGBME were studied.The content of the product was analyzed by GC and the structure of the prod- uct was characterized by FT-IR and ~1H NMR.The optimal conditions for the synthesis of DGBME were found as follows:reaction temperature 80℃,reaction time 4.0 h and n (n-C_4H_9Br)/ n(C_5H_(12)O_3)=1.06:1.Under the optimal conditions,the yield of DGBME was 92.14 % and the con- tent of DGBME in the product was above 99.5%.