Crystal Structure of [Aqua (2, 2-bipyridine) (6-carboxypyridine-2-carboxylato] copper (II) Nitrate Monohydrate Complex at 150 K

The reaction of copper (II) nitrate with pyridine-2,6-dicarboxylic acid, (pydcH2) and 2,2-bipyridine (2,2-bipy) led to the formation of the title compound, [Cu(C7H4NO4)(C10H8N2)(H2O)]NO3.H2O, or [Cu(pydcH)(2,2-bipy)(H2O)]NO3.H2O. The crystal system of the complex is triclinic with space group P and two molecules per unit cell. The unit cell parameters are: a = 7.0438 (6) Å, b = 11.3215 (10) Å, c = 12.9148 (9) Å, a = 107.498 (4)°, ß = 94.557 (5)° and? = 104.325 (5)°. The final R value was 0.03 for 3601 observed reflections. The cationic complex features six-coordinate CuII with a distorted octahedral geometry with a significantly longer Cu1—O4 bond [2.5491(16) Å]. Considerable C-O•••p stacking interactions between the C-O groups with distance of 3.498 (2) Å are observed. In addition, distinct intermolecular O—H•••O and N—H•••O hydrogen bonds lead to the formation of R (12) and C (12) graph sets motifs. In the crystal structure, a wide range of non-covalent interactions consisting of hydrogen bonding (O—H•••O, O—H•••N and C—H•••O), p–p [centroid–centroid distances of 3.5193 (13) Å and 3.6876 (13) Å] and C-O•••p stacking interactions connect the various components into a supramolecular structure.