Crystal structure of tetra-kis-[μ-2-(meth-oxy-carbon-yl)benzoato-κ 2 O 1 : O 1' ]bis-[( N , N -di-methyl-formamide-κ O )copper(II)]( Cu - Cu ) di-methyl-formamide disolvate.

The title compound, [Cu2 (C9 H7 O4 )4 (C3 H7 NO)2 ]·2C3 H7 NO, crystallizes in the monoclinic P 21 / c space group, with the binuclear copper unit occupying a special position on an inversion center, i.e. the asymmetric unit of the crystal consists of one CuII ion, two 2-(meth-oxy-carbon-yl)benzoate ligands, and two DMF mol-ecules (one coordinated and one solvate). The binuclear complex displays a paddle-wheel-shaped structure with the two copper atoms being in a Jahn-Teller-distorted octa-hedral coordination environment. Each 2-(meth-oxy-carbon-yl)benzoate substituent acts as a bridging ligand and links two Cu atoms with a Cu-Cu distance of 2.633 (1) Å. The carboxyl-ate groups of the 2-(meth-oxy-carbon-yl)benzoate ligands adopt bidentate syn - syn bridging modes, with dihedral angles between the carboxyl-ate planes and the aromatic rings of 18.427 (4) and 43.029 (6)°. In the crystal, adjacent DMF mol-ecules coordinated to copper atoms are arranged in a mutual 'head-to-tail' manner by offset face-to-face π-π stacking inter-actions, resulting in chains along the c- axis direction. The planes of the coordinated DMF mol-ecules are parallel to each other, the distance between them being 3.33 (1) Å. A three-dimensional structure is assembled from the chains by weak C-H⋯O and C-H⋯π inter-molecular inter-actions involving the DMF solvent mol-ecules. One of the methyl ester groups is disordered over two sites with an occupancy ratio of 0.751 (12):0.249 (12).