Crystal structure of a looped-chain CoIIcoordination polymer:catena-poly[[bis(nitrato-κO)cobalt(II)]bis[μ-bis(pyridin-3-ylmethyl)sulfane-κ2N:N′]]

Abstract

The asymmetric unit of the title compound, [Co(NO3)2(C12H12N2S)2]n, contains a bis(pyridin-3-ylmethyl)sulfane (L) ligand, an NO3−anion and half a CoIIcation, which lies on an inversion centre. The CoIIcation is six-coordinated, being bound to four pyridine N atoms from four symmetry-relatedLligands. The remaining coordination sites are occupied by two O atoms from two symmetry-related nitrate anions in a monodentate manner. Thus, the CoIIcentre adopts a distorted octahedral geometry. Two symmetry-relatedLligands are connected by two symmetry-related CoIIcations, forming a 20-membered cyclic dimer, in which the CoIIatoms are separated by 10.2922 (7) Å. The cyclic dimers are connected to each other by sharing CoIIatoms, giving rise to the formation of an infinite looped chain propagating along the [101] direction. Intermolecular C—H...π (H...ring centroid = 2.89 Å) interactions between one pair of correspondingLligands and C—H...O hydrogen bonds between theLligands and the nitrate anions occur in the looped chain. In the crystal, adjacent looped chains are connected by intermolecular π–π stacking interactions [centroid-to-centroid distance = 3.8859 (14) Å] and C—H...π hydrogen bonds (H...ring centroid = 2.65 Å), leading to the formation of layers parallel to (101). These layers are further connected through C—H...O hydrogen bonds between the layers, resulting in the formation of a three-dimensional supramolecular architecture.