Crystal structure of trans-diaquabis(4-cyanobenzoato-κO)bis(nicotinamide-κN1)cobalt(II)

In the title complex, [Co(C8H4NO2)2(C6H6N2O)2(H2O)2], the CoII atom is located on an inversion centre and is coordinated by two 4-cyanobenzoate (CNB) anions, two nicotinamide (NA) ligands and two water molecules. The four O atoms in the equatorial plane form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination sphere is completed by the two N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxylate group and the adjacent benzene ring is 22.11 (15)°, while the pyridine and benzene rings are oriented at a dihedral angle of 89.98 (5)°. In the crystal, intermolecular N—H...O and O—H...O hydrogen bonds link the molecules, enclosing R22(8) and R44(8) ring motifs, forming layers parallel to (100). The layers are linked via C—H...O and C—H...N hydrogen bonds, resulting in a three-dimensional network. A weak C—H...π interaction is also observed.