[double_bond]

;hi..all 

   reaction between o-Phenylendiamine and formic acid yield benzimidazole ,can we use other aromatic acid insted of formic acid to get substituted imidazole. please give your valuable suggestions to perform the reaction between o-Phenylendiamine and salicylic acid.

here is the reference

Org. Syn. Coll. Vol. 2, 501

http://orgsyn.org/orgsyn/default.asp?formgroup=basenpe_form_group&dataaction=db&dbname=orgsyn

clik the link and type    benzimidazole then you get the preperation of benzimidazole

[DavidW]

You might want to check this reference out:

Journal of Hetereocyclic Chemistry, 1981, 18(4), 803-5. 

They have procedures for the reaction between o-phenylenediamine and salicylic acid to form the corresponding benzimidazole