Zn-Proline Catalyzed Selective Synthesis of 1,2-Disubstituted Benzimidazoles in Water

Abstract

Zn-proline (5 mol%) performs as a novel water-soluble and recyclable Lewis acid catalyst for the selective synthesis of 1,2-disubstituted benzimidazoles from wide range of substituted o-phenylenediamines and aldehydes in moderate to excellent isolated yields (42—92%) using water as solvent at ambient temperature.