New route for the synthesis of benzimidazoles by a one-pot multistep process with mono and bifunctional solid catalysts

One-pot multistep reactions involving a new environmentally friendly catalytic procedure have been developed for the synthesis of benzimidazoles. Benzimidazole derivatives with biological and pharmaceutical interest have been prepared by a one-pot four step process with a solid catalyst containing basic and oxidation sites. The four steps refer to: (a) oxidation of the alcohol; (b) cyclocondensation of the aldehyde formed with ortho-phenylenediamines, (c) oxidation of the carbon-nitrogen bond, (d) N-alkylation reaction. The process is illustrated by the synthesis of 1,2-disubstituted benzimidazole derivative with antiviral activity.