Bis(μ-4-formylbenzoato-κ² O:O′)bis[(4- formylbenzoato-κ² O,O′)bis(isonicotinamide-κN ¹)copper(II)]

The asymmetric unit of the centrosymmetric dinuclear title compound, [Cu₂(C₈H₅O₃)₄(C ₆H₆N₂O)₄], contains one half of the complex molecule. The Cu^II atoms are bridged by the carboxylate groups of two 4-formylbenzoate (FOB) anions. Besides the two bridging FOB anions, one additional chelating FOB anion and two isonicotinamide (INA) ligands complete the distorted CuN₂O₄ octahedral coordination of each Cu²⁺ cation. Within the asymmetric unit, the benzene and pyridine rings are oriented at dihedral angles of 25.1 (3) and 12.6 (3)°, respectively. In the crystal, N - H⋯O and C - H⋯O hydrogen bonds link the molecules into a three-dimensional network. π-π contacts between the pyridine rings [shortest centroid-centroid distance = 3.821 (3) Å] may further stabilize the crystal structure. One of the formyl groups of the two FOB anions is disordered over two sets of sites with an occupancy ratio of 0.65:0.35.