N-乙基-N-异丁基间氨基苯酚的合成研究

Synthesis Research of N-ethyl-N-isobutyl-m-aminophenol

N-乙基-N-异丁基间氨基苯酚是一种重要的荧烷类压热敏染料中间体,国内尚没有其合成方法的报道.以N-乙基间氨基苯酚为原料,溴代异丁烷为烷基化剂,三乙胺为缚酸剂,四氢呋喃为溶剂,采用烷基化法合成N-乙基-N-异丁基间氨基苯酚,反应在水热釜(密闭不锈钢釜)中进行.通过TLC对反应进程进行检测,并详细讨论了温度、时间、物料摩尔比对反应的影响.经反复实验得出较好的反应条件:n(间氨基苯酚)∶n(溴代异丁烷)∶n(三乙胺)为1∶1. 75∶0. 6,反应温度115℃,反应时间30 h,产物收率88%,纯度为89. 7%(面积归一法).粗产物通过柱层析方法进行分离提纯,淋洗剂为V(石油醚)∶V(乙酸乙酯)=4∶1,提纯后的产品纯度为95%,经红外光谱和紫外光谱分析确认所合成物质为N-乙基-N-异丁基间氨基苯酚.

N-ethyl-N-isobutyl-m-aminophenol is a very important intermediate of fluorane pressurethermosensitive dyes,and there is no synthetic report in China. In this paper,N-ethyl interaminophenol was used as rawmaterial,bromoisobutane as alkylation agent,triethylamine as binding acid agent and N-ethylN-isobutyl-m-aminophenol was synthesized by alkylation method. The reaction was carried out in a hydrothermalreactor(closed stainless steel reactor),TLC was used to monitor the reaction process. The effect of temperature,time and material ratio were discussed in detail and the best reaction condition was determined. After repeated trials,better reaction conditions were obtained: the optimal molar ratio between amino phenol,isobutyl bromide and triethylamine was 1∶ 1. 75∶ 0. 6,the reaction temperature was 115 ℃,and the reaction time was 30 h,then the yield of product was 88 %,TLCS was used to detect the purity of N-ethyl-N-isobutyl-m-aminophenol and the purity reached 89. 7 %(area normalization method). The crude product was separated and purified by column chromatography. The leaching agent was petroleum ether∶ ethyl acetate = 4∶ 1. After purification,the purity of the product was 95 %,and the product was N-ethyl-N-isobutyl-m-aminophenol confirmed by IR and UV.