Synthesis of 5-aryl-$N$-(trichloroacetyl)-1,3,4-oxadiazole-2-carboxamide via three-component reaction of trichloroacetyl isocyanate, ($N$-isocyanimino)triphenylphosphorane, and benzoic acid derivatives

The three-component reaction of benzoic acid derivatives, ($N$-isocyanimino)triphenylphosphorane, and trichloroacetyl isocyanate in a 1:1:1 ratio in CH$_{3}$CN occurred at room temperature, and the 5-aryl-$N$-(trichloroacetyl)-1,3,4-oxadiazole-2-carboxamide derivatives produced were formed in high yields. The reaction proceeded smoothly and cleanly under mild reaction conditions and no side reactions were observed. The structures of the products were confirmed by IR, $^{1}$H NMR, $^{13}$C NMR, mass spectroscopy, and elemental analysis.