Copper-Catalyzed Intramolecular Cyclization to N-Substituted 1,3-Dihydrobenzimidazol-2-ones
摘要:
An efficient and convenient method was developed for preparing N-substituted 1,3-dihydrobenzimidazol-2-ones from N'-substituted N-(2-halophenyl)ureas via a Cul/DBU-catalyzed cyclization in DMSO under microwave heating. High yields were obtained and a variety of functional groups were tolerated under these conditions, including N'-aryl, alkyl, heterocyclic, various N-(substituted 2-halophenyl) and N-(2-iodopyridyl)ureas.