3-Allyl-1-(3-cyano-phenyl-methyl-ene)-2-methyl-1H-benzoimidazol-3-ium bromide monohydrate.

In the title compound, C(19)H(18)N(3) (+)·Br(-)·H(2)O, the dihedral angle between the allyl group and the imidazole ring is 89.59 (14)°, while the dihedral angle between the cyanophenyl ring and the imidazole ring is 78.72 (7)°. O-H⋯Br hydrogen bonds form an infinite chain in the c-axis direction and C-H⋯Br and C-H⋯O inter-actions expand this chain into an infinite three-dimensional network.

3-Allyl-1-(2-cyano-benz-yl)-2-methyl-benzimidazol-3-ium bromide.

In the title compound, C(19)H(18)N(3) (+)·Br(-), both the allyl and cyano-phenyl groups are approximately perpendicular to the central benzimidazole unit, making dihedral angles of 89.7 (2) and 85.09 (13)°, respectively. The crystal packing is dominated by C-H⋯Br inter-actions, with each anion inter-acting with five neighboring cations.