Crystal Structure of Tetra­kis­([mu]-2,4,6-Tri­methyl­benzoato-[Kappa]2O:O')Bis­[(Nicotinamide-[kN1)Copper(II)]

Abstract

In the title binuclear Cu II complex, [Cu 2 (C 10 H 11 O 2 ) 4 (C 6 H 6 N 2 O) 2 ], the two Cu II cations [Cu...Cu = 2.5990 (5) Å] are bridged by four 2,4,6-trimethylbenzoate (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 molecules 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 molecule, the dihedral angles between the planes of the benzene rings and the adjacent carboxylate 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 molecules, 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 molecule located within this void. The crystal studied was an inversion twin refined with a minor component of 0.488 (8).