Crystal structure of tetra-kis-(μ-2,4,6-tri-methyl-benzoato-κ(2) O:O')bis-[(nicotinamide-κN (1))copper(II)]

In the title binuclear Cu(II) complex, [Cu2(C10H11O2)4(C6H6N2O)2], the two Cu(II) cations [Cu⋯Cu = 2.5990 (5) Å] are bridged by four 2,4,6-tri-methyl-benzoate (TMB) anions. The four nearest O atoms around each Cu(II) cation form distorted square-planar arrangements and the distorted square-pyramidal coordinations are completed by the pyridine N atoms of nicotinamide mol-ecules at distances of 2.164 (2) and 2.165 (2) Å, respectively. The Cu(II) cations are displaced by -0.2045 (3) and 0.2029 (3) Å from the corresponding planes formed by the nearest four O atoms. In the mol-ecule, the dihedral angles between the planes of the benzene rings and the adjacent carboxyl-ate groups are 80.6 (2), 51.4 (2), 24.4 (2) and 32.5 (2)°, while the planes of the pyridine rings are oriented at a dihedral angle of 11.28 (10)°. In the crystal, bifurcated N-H⋯O and weak C-H⋯O hydrogen bonds link the mol-ecules, enclosing R 2 (2)(8) and R 4 (4)(8) ring motifs, into a three-dimensional network. The structure contains a solvent-accessible void of 72 Å(3), but there is no solvent mol-ecule located within this void. The crystal studied was an inversion twin refined with a minor component of 0.488 (8).