by the reaction of 5-phenyl-1,3,4-oxadiazole-2(3H)-thione with trichloromethyl chloroformate in benzene. The reagent 3 was found to be very useful for the one-pot or direct preparation of amide, ester, thiol ester, urea, and carbonate under mild conditions. The one-pot or direct polycondensation of several dicarboxylic acids with aromatic diamines and of aromatic diamines using 3 proceeded smoothly
一种新型
缩合剂 3,3'-羰基双 [5-苯基-1,3,4-恶二唑-2(3H)-
硫酮] (3),很容易通过 5-苯基-1,3 的反应制备, 4-恶二唑-2(3H)-
硫酮与
氯甲酸三氯甲酯的苯溶液。发现试剂3对于在温和条件下一锅法或直接制备酰胺、酯、
硫羟酸酯、
尿素和
碳酸酯非常有用。几种二元
羧酸与芳族二胺和芳族二胺的一锅或直接缩聚反应在室温下顺利进行,分别制备高分子量聚酰胺和聚
脲。