Condensation reactions of benzils with ureas in ethylene glycol
作者:Chang Kiu Lee、Sun Hee Kim、Yong Bun Kim
DOI:10.1002/jhet.5570330403
日期:1996.7
Reactions of benzils and urea in ethylene glycol at 180° for 1-2 hours gave 2,4,5-triaryloxazoles as major products and bicyclic imidazoimidazole-2,5-diones as minor products. N-Methylurea and N-phenylurea gave the oxazoles under similar conditions. The solvent seemed to assist the formation of oxazole by eliminating the isocyanate components as ethylene glycol biscarbamates.