Synthesis of benzimidazoles by Cu2O-catalyzed cascade reactions between o-haloaniline and amidine hydrochlorides
作者:Yanyang Qu、Lei Pan、Zhiqing Wu、Xiangge Zhou
DOI:10.1016/j.tet.2012.12.039
日期:2013.2
An efficient Cu2O-catalyzed method for the synthesis of benzimidazole derivatives from amidinehydrochlorides and o-haloaniline has been developed. The cascade C–N coupling and intramolecular transamination reaction provided benzimidazole derivatives in high yields up to 90%.
An efficientapproach to the synthesis of benzimidazole derivatives has been achieved by copper-catalyzed double C–N bonds formation of N-alkyl-2-iodoaniline and sodium azide. The reaction was supposed to proceed throughcopper-catalyzed tandem reaction of SNAr reaction, aerobic oxidation of C(sp3)–H bond and intramolecular C–N bond formation sequence. Structurally diverse 2-aryl, alkenyl and alkyl