Synthesis and crystal structure of poly[[bis­(aqua-κO)tetra­kis­(μ-4,4′-bi­pyridine-κ2N:N′)hexa­kis­(3-chloro­benzoato)-κ5O;κ2O:O′-tricobalt(II)] methanol disolvate]

A novel ladder-chain cobalt(II) coordination polymer, {[Co3(C7H4ClO2)6(C10H8N2)4(H2O)2]·2CH3OH}n, was synthesized and characterized. The structure contains two CoII centres with different octa­hedral environments, [Co(1)N3O3] and [Co(2)N2O4]. The O-donating 3-chloro­benzoate anions (3-Clbenz) act as the terminal ligands, while the N-donating 4,4′-bipy mol­ecules play the role of linkers. The Co(1) ions are linked by 4,4′-bipy mol­ecules into linear chains. Two such chains are joined by [Co(2)(3-Clbenz)2(H2O)2] units via two 4,4′-bipy bridging ligands, thus forming the ladder-chain structure. The crystal packing of the title compound is stabilized by supra­molecular inter­actions, such as hydrogen bonding, π–π and halogen⋯π contacts, giving a three-dimensional framework. The spectroscopic and thermal properties of the title compound have also been investigated.