Crystal structure of a CoII coordination polymer with a dipyridyl ligand: catena-poly[[bis(nitrato-κ2O,O′)cobalt(II)]-μ-N-(pyridin-2-ylmethyl)pyridine-3-amine-κ3N,N′:N′′]

The asymmetric unit of the title compound, [Co(NO3)2L]n, L = N-(pyridine-2-ylmethyl)pyridine-3-amine (C11H11N3), contains one CoII centre, two nitrate anions and one L ligand in which the Cpy—C—N—Cpy moiety adopts a trans conformation with a torsion angle of −173.1 (3) Å. The coordination geometry of the CoII atom is a distorted pentagonal bipyramid. One amine N atom from the L ligand and four O atoms from two η2-nitrato ligands form the basal plane and two pyridyl N atoms from two symmetry-related L ligands occupy the apical positions [N—Co—N = 171.86 (11)°]. The displacement of the central CoII atom from the basal plane (r.m.s. deviation = 0.085 Å) is 0.1491 (12) Å. Each bidentate nitrate group is bonded asymmetrically to the cobalt atom in an chelating fashion. The CoII ions are linked by the L ligands to form a zigzag chain propagating along the c-axis direction. Within the zigzag chain, C—H...O hydrogen bonds between the ligands and the nitrate anions are observed. Adjacent zigzag chains are connected via intermolecular π–π stacking interactions [centroid-to-centroid distance = 3.844 (2) Å] between the pyridine rings together with N/C—H...O hydrogen bonds