1428668-36-3Relevant articles and documents
Multistep divergent synthesis of benzimidazole linked benzoxazole/ benzothiazole via copper catalyzed domino annulation
Liao, Jen-Yu,Selvaraju, Manikandan,Chen, Chih-Hau,Sun, Chung-Ming
, p. 2473 - 2481 (2013/06/04)
An efficient, facile synthesis of structurally diverse benzimidazole integrated benzoxazole and benzothiazoles has been developed. In a multi-step synthetic sequence, 4-fluoro-3-nitrobenzoic acid was converted into benzimidazole bis-heterocycles, via the intermediacy of benzimidazole linked ortho-chloro amines. The amphiphilic reactivity of this intermediate was designed to achieve the title compounds by the reaction of various acid chlorides and isothiocyanates in a single step through the in situ formation of ortho-chloro anilides and thioureas under microwave irradiation. A versatile one pot domino annulation reaction was developed to involve the reaction of benzimidazole linked ortho-chloro amines with acid chlorides and isothiocyanates. The initial acylation and urea formation followed by copper catalyzed intramolecular C-O and C-S cross coupling reactions furnished the angularly oriented bis-heterocycles which bear a close resemblance to the streptomyces antibiotic UK-1. The Royal Society of Chemistry 2013.