1 Amino 6 chloro 2 (1 H pyrrol 2 yl)benzimidazole (RS 1350)

The title compound (RS 1350), C11H9ClN4, was recently synthesized by a Smiles rearrangement of 1-[(5-chloro-2-nitro­phenyl)­sulfonyl]-1H-pyrrole-2-carbohydrazide or 1-(5-chloro-2-nitro­phenyl)-1H-pyrrole-2-carbohydrazide in pow­der­ed iron-glacial acetic acid medium. From the crystallographic analysis, it is observed that, in the title compound, the benz­imidazole moiety is planar and forms a dihedral angle of 3.8 (2)° with the pyrrole ring. The near planarity of the two rings indicates an extended conjugation.