1,1',2,2'-Tetra-methyl-3,3'-(p-phenyl-enedimethyl-ene)diimidazol-1-ium dibromide

The title imidazolium-based ionic-liquid salt, C(18)H(24)N(4) (2+)·2Br(-), has the cation lying about a center of inversion. The five-membered imidazole ring is disordered over two positions with the major component having a site occupancy of 0.712 (4); the N-bound methyl substituents are ordered. The imidazole ring is approximately perpendicular to the six-membered phenyl-ene ring [dihedral angle = 80.7 (5)° for the major disorder component and 89.8 (3)° for the other; the two components are off-set by 10.1 (6)°].