A novel one‐dimensional coordination polymer,catena‐poly[[diaquacobalt(II)]‐μ‐(2,2′‐bipyridyl‐3,3′‐dicarboxylato‐κ4N,N′:O,O′)]

The title compound, Co(C₁₂H₆N₂O₄)(H₂O)₂]_n, has been hydro­thermally synthesized and structurally characterized. It consists of polymeric chains of Co{μ‐(2,2′‐bipyridyl‐3,3′‐di­carboxyl­ato‐κ⁴N,N′:O,O′)}(H₂O)₂] units, in which each Co^II cation is octahedrally coordinated by two chelating pyridyl N atoms, two chelating carboxyl O atoms from different carboxylate groups of another bipyridyl ligand, and two water mol­ecules as terminal ligands. A crystallographic twofold axis parallel to the chain axis, passes through the Co atom.