摘要
分别以无水氯化锌、对甲苯磺酸为催化剂,采用微波辐射法,在无溶剂条件下由4-氯间苯二酚与三氟乙酰乙酸乙酯缩合制备标题化合物;优化了反应条件.结果表明,在微波辐射下,无水氯化锌对该反应有较好的催化活性,相应的4-三氟甲基-7-羟基-6-氯香豆素的产率可达73.0%.优化的反应条件为:4-氯间苯二酚、三氟乙酰乙酸乙酯和无水ZnCl2的摩尔比为1∶1.1∶0.9,微波辐射功率800W,辐射时间20min,反应温度85℃.
4-trifluoromethyl-7-hydroxyl-6-chlorine coumarin was synthesized by the reaction of 4-chlororesorcinol with ethyl trifluoroacetoacetate under microwave irradiation and solvent-free condition in the presence of zinc chloride anhydrous or p-toluene sulfonic acid as the catalyst. The optimized faction condition was established. It has been found that zinc chloride anhydrous as an efficient Lewis acid catalyst for Pechmann reaction is able to well catalyze the reaction of 4-chlororesorcinol with ethyl trifluoroacetoacetate under microwave irradiation, affording 4-trifluoromethyl-7-hydroxyl-6-chlorine coumarin in a yield of 73%. The optimal molar ratio of 4- chlororesorcinol/ethyl trifluoroacetoacetate/zinc chloride anhydrous is suggested to be 1: 1. 1 : 0.9, and the optimal reaction condition is established as a microwave power of 800 W, a reaction time of 20 min, and a reaction temperature of 85℃.
出处
《化学研究》
CAS
2012年第5期12-15,共4页
Chemical Research
基金
宝鸡文理学院重点项目(ZK10129)
关键词
无水氯化锌
对甲苯磺酸
4-氯间苯二酚
三氟乙酰乙酸乙酯
微波辐射
固相合成
zinc chloride anhydrous
p-toluene sulfonic acid
4-chlororesorcinol
ethyl trifluoracetoacetate
microwave irradiation
solid-phase synthesis