Benzimidazole and their derivatives have diverse applications in medicinal chemistry because of their unique biological and pharmacological activities. Many members of this family have commercial applications in various realms of therapy, including antiulcerative, antihypertensive, antiviral, antifungal, antitumor and antihistaminic agents and antihelminthic agents in veterinary medicine [1][2][3][4][5][6][7] . Due to their affinity towards enzymes and protein receptors, they have been appropriately classified as 'privileged sub-structures' for drug design. Moreover, benzimidazoles are very important intermediates in various organic reactions 8 . Therefore, the preparation of benzimidazoles has received considerable attention in recent years.Until now, many synthetic strategies for the preparation of benzimidazoles have been reported in the literature. Generally, they are synthesized through the condensation reaction of o-phenylenediamines and carboxylic acids or their derivatives (nitriles, amidates, orthoesters) 9 in the presence of strong acids such as polyphosphoric acid 10 or mineral acids 11 . Benzimidazoles have also been prepared by the condensation reaction of aldehyde and arylenediamine under oxidative conditions [12][13][14][15] . However, each of these methodologies suffer from one or more shortcomings, such as low yields, long reaction times, using toxic catalyst and solvents, tedious workup procedures and co-occurrence of several side reactions.Organic reactions in aqueous media have attracted great interest due to its safety, low cost and environmental friendly 16 .