1,1′,2,2′-Tetramethyl-3,3′-(p-phenylenedimethylene)diimidazol-1-ium dibromide

The title imidazolium-based ionic-liquid salt, C18H24N4 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 phenylene 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)°].

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