Diaquabis(4-bromobenzoato-kappa O)bis(N,N-diethylnicotinamide-kappa N-1)copper(II)

The title Cu-II complex, [Cu(C7H4BrO2)(2)(C10H14N2O)(2)-(H2O)(2)], contains two 4-bromobenzoate (PBB), two diethylnicotinamide (DENA) monodentate ligands and two water molecules. The four O atoms in the equatorial plane around the Cu-II ion form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination is completed by two N atoms of the DENA ligands in the axial positions. Intramolecular O-H center dot center dot center dot O hydrogen bonds link the water molecules to the carboxylate groups. The dihedral angles between the carboxylate groups and the adjacent benzene rings are 3.1 (3) and 3.74 (17)degrees, while the pyridine rings and the benzene rings are oriented at dihedral angles of 6.81 (10) and 3.38 (12)degrees. In the crystal, intermolecular O-H center dot center dot center dot O hydrogen bonds link the molecules into double chains along the b axis. C-H center dot center dot center dot O interactions are also observed. pi-pi contacts between pyridine rings [centroid-centroid distance = 3.485 (2) angstrom] may further stabilize the crystal structure.