Jm. Gardiner et al., SYNTHESIS OF 1-ALKOXY-2-ALKYL-BENZIMIDAZOLES FROM 2-NITROANILINES VIATANDEM N-ALKYLATION-CYCLIZATION-O-ALKYLATION, Tetrahedron, 51(14), 1995, pp. 4101-4110
Substituted 2-nitroanilines react with benzylic, allyl and alkyl halid
es to give 2-aryl-1-benzyloxy-, 1-allyloxy-2-vinyl- and 1-alkoxy-2-alk
yl-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 (79-98%), while with simple a
lkyl halides, yields of the benzimidazoles are substrate dependent. An
X-ray crystal structure of 2,4-dimethyl-1-ethoxybenzimidazole is pres
ented.