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800 W,辐射时间20 min,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-touene sulfonic acid as the catalyst. The optimized raction 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-tri-fluoromethyl-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, are-action time of 20 min, and a reaction temperature of 85 ℃.
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