摘要
2,6-二氯甲苯(2,6-Dichlorotoluene)是一种重要的有机合成原料及精细化工中间体,由它出发可以合成系列精细化工产品,如杀菌剂、除草剂、染料和颜料、医药等。2,6-二氯甲苯的地位和作用已经逐渐受到人们的重视,选择合适的制备2,6-二氯甲苯的方法是关注的焦点,提高甲苯环氯化过程中目标产物的含量成为合成技术的关键。本文采用对甲苯磺酸定向氯化的方法制备2,6-二氯甲苯,具体方法为以对甲苯磺酸为原料,以氯气为氯源,在塔式反应器中进行定向氯化。考察了不同催化剂,不同反应温度及不同反应时间等因素对产物选择性的影响。实验结果表明:在以FeCl_3为催化剂,反应温度为60℃,反应时间为5小时的条件下,对甲苯磺酸转化率为100%,2,6-二氯甲苯的选择性可达到56.7%。
2,6-dichlorotoluene is an important raw material in organic synthesis and fine chemical intermediates.A series of fine chemical products can be synthesized starting from it.It has attracted people's attention because of its function and extensive use.Selecting an appropriate preparation method of 2,6-dichlorotoluene is the focus of people's attention.It is the key that how to improve the content of target product in the process of cyclic-chlorination to the synthesis technology.In this essay,2,6-dichlorotoluene was synthesized by orientation chlorination method with the p-toluene sulfonic acid as the starting material and chlorine as chlorine source in the tower-type reactor.The influences of different catalysts,reaction temperature and reaction duration on the selectivity were investigated.The experimental results showed that under the condition of FeCl_3 as the catalyst,temperature 60℃,reaction time 5h,the conversion of p-toluene sulfonic acid is 100%,the selectivity of 2,6-dichlorotoluene can reach 56.7%.
引文
[1]Sudip Mukhopadhyay,Jayanta K.Mukhopadhyaya,Datta E.Ponde,Shlomo Cohen,and Basan G.S.Kurkalli.Org.Process Res.Dev.2000,4(6):509.
[2]方永勤,吕春绪,陈群,范正明.化工进展,2002,21(9):656.