Poly[[diaqua­bis­{μ-4-[6-(4-carb­oxy­phen­yl)-4,4′-bipyridin-2-yl]benzoato-κ(2) O:N (1′)}copper(II)] dimethyl­formamide tetra­solvate]

In the title compound, {[Cu(C(24)H(15)N(2)O(4))(2)(H(2)O)(2)]·4C(3)H(7)NO}(n), the Cu(II) ion, lying on an inversion center, is six-coordinated by two N atoms from two 4-[6-(4-carb­oxy­phen­yl)-4,4′-bipyridin-2-yl]benzoate (L) ligands, two deprotonated carboxyl­ate O atoms from two other symmetry-related L ligands and two water mol­ecules in a slightly distorted octa­hedral geometry. The Cu(II) atoms are linked by the bridging ligands into a layer parallel to (101). The presence of intra­layer O—H⋯O hydrogen bonds and π–π inter­actions between the pyridine and benzene rings [centroid–centroid distances = 3.808 (2) and 3.927 (2) Å] stabilizes the layer. Further O—H⋯O hydrogen bonds link the layers and the dimethyl­formamide solvent mol­ecules.