Bis{4-[(E)-2-(1H-indol-3-yl)ethenyl]-1-methylpyridinium} 4-chlorobenzenesulfonate nitrate

Abstract

In the title mixed salt, 2C16H15N2+·C6H4ClO3S−·NO3−, one of the cations shows whole molecule disorder over two sets of sites in a 0.711 (7):0.289 (7) ratio. The 4-chorobenzenesulfonate anion is also disordered over two orientations in a 0.503 (6):0.497 (6) ratio. The cations are close to planar, the dihedral angles between the pyridinium and indole rings being 1.48 (3)° in the ordered cation, and 5.62 (3) and 2.45 (3)°, respectively, for the major and minor components of the disordered cation. In the crystal, the cations are stacked in an antiparallel manner approximately along thea-axis direction and linked with the anionsviaN—H...O hydrogen bonds and C—H...O interactions, generating a three-dimensional network. Weak C—H...π and π–π interactions [with centroid–centroid distances of 3.561 (2)–3.969 (7) Å] are also observed.