3,3′-carbonylbis[5-phenyl-1,3,4-oxadiazole-2(3<i>H</i>)-thione]: A Novel, Reactive, and Versatile Condensing Agent for Amide, Ester, Thiol Ester, Urea, Carbonate, Polyamide, and Polyurea Syntheses

Abstract

Abstract A novel condensing agent, 3,3′-carbonylbis[5-phenyl-1,3,4-oxadiazole-2(3H)-thione] (3), was readily prepared 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 at ambient temperature to produce high-molecular-weight polyamides and polyureas, respectively.