Selenium-catalyzed carbonylation of 2-aminothiazole with nitro aromatics to N-aryl-N′-2-thiazolylureas

Abstract

An efficient, economical, and phosgene-free procedure for the synthesis of N-aryl-N′-2-thiazolylureas is reported. With cheap and recyclable nonmetal selenium instead of noble metals as the catalyst, carbon monoxide instead of virulent phosgene as the carbonylation agent, the selenium-catalyzed carbonylation reaction of 2-aminothiazole can proceed smoothly in one-pot manner with a variety of nitro aromatics in the presence of triethylamine to afford the desired N-aryl-N′-2-thiazolylureas mostly in moderate to good yields. Selenium catalyst can be easily recovered due to its phase-transfer catalytic ability and reused without any significant degradation of its catalytic performance.