Crystal structure of di-μ-chlorido-bis­­[chlorido­bis­­(1,2-di­methyl-5-nitro-1H-imidazole-κN3)copper(II)] aceto­nitrile disolvate

1,2-Dimethyl-5-nitro­imidazole (dimetridazole, dimet) is a compound that belongs to a class of nitro­imidazole drugs that are effective at inhibiting the activity of certain parasites and bacteria. However, there are few reports that describe structures of compounds that feature metals complexed by dimet. Therefore, we report here that dimet reacts with CuCl2·H2O to yield a chloride-bridged copper(II) dimer, [Cu2Cl4(C5H7N3O2)4] or [Cu(μ-Cl)Cl(dimet)2]2. In this mol­ecule, the CuII ions are coordinated in an approximately trigonal–bipyramidal manner, and the mol­ecule lies across an inversion center. The dihedral angle between the imidazole rings in the asymmetric unit is 4.28 (7)°. Compared to metronidazole, dimetridazole lacks the hy­droxy­ethyl group, and thus cannot form inter­molecular O⋯H hydrogen-bonding inter­actions. Instead, [Cu(μ-Cl)Cl(dimet)2]2 exhibits weak inter­molecular inter­actions between the hydrogen atoms of C—H groups and (i) oxygen in the nitro groups, and (ii) the terminal and bridging chloride ligands. The unit cell contains four disordered aceto­nitrile mol­ecules. These were modeled as providing a diffuse contribution to the overall scattering by SQUEEZE [Spek (2015[Spek, A. L. (2015). Acta Cryst. C71, 9-18.]). Acta Cryst. C71, 9–18], which identified two voids, each with a volume of 163 Å3 and a count of 46 electrons, indicative of a total of four aceto­nitrile mol­ecules. These aceto­nitrile mol­ecules are included in the chemical formula to give the expected calculated density and F(000).