Synthesis of 1-Alkoxy-2-Alkyl-Benzimidazoles from 2-Nitroanilines via Tandem N-Alkylation-Cyclization-O-Alkylation

Article abstract of DOI:10.1016/0040-4020(95)00127-T

Substituted 2-nitroanilines react with benzylic, allyl and alkyl halides to give 2-aryl-1-benzyloxy-, 1-allyloxy-2-vinyl- and 1-alkoxy-2-alkyl-benzimidazoles, in a one-pot cascade process involving 1-alkylation-cyclization-O-alkylation. 2-Aryl-1-benzyloxy- and 1-allyloxy-2-vinyl- derivatives are obtained in high yields (79-98percent), while with simple alkyl halides, yields of the benzimidazoles are substrate dependent.An X-ray crystal structure of 2,4-dimethyl-1-ethoxybenzimidazole is presented.