Bis[3-allyl-1-(4-cyanobenzyl)-2-methylbenzimidazolium] di-μ-bromido-bis[bromidocuprate(I)]

Abstract

The asymmetric unit of the title compound, (C19H18N3)2[Cu2Br4], contains one cation and one half-anion; there is a centre of symmetry mid-way between the two Cu atoms. In the cation, the nearly planar benzimidazole ring system is oriented at dihedral angles of 75.31 (3) and 21.39 (3)° with respect to the cyanobenzyl and allyl groups, respectively. The dihedral angle between cyanobenzyl and allyl groups is 87.94 (3)°. In the crystal structure, intermolecular C—H...Br hydrogen bonds link the molecules. There is a C—H...π contact between the cyanobenzyl ring and the anion; π—π contacts also exist between the benzimidazole ring systems as well as between the anion and the cyanobenzyl ring [centroid–centroid distances = 4.024 (1) and 4.617 (1) Å, respectively].