catena-Poly[[(2,2′-bipyridine-κ(2) N,N′)cadmium]-μ(3)-4-nitro­phthalato-κ(4) O:O′,O′′:O′′′]

In the title polymeric compound, [Cd(C(8)H(3)NO(6))(C(10)H(8)N(2))](n), two O atoms from both carboxyl­ate groups of a nitro­phthalate anion coordinate to the Cd(II) cation, forming a seven-membered chelate ring and two carboxyl­ate O atoms from another two nitro­phthalate anions and a 2,2′-bipyridine ligand coordinate to the Cd cation to complete the distorted octa­hedral coordination geometry. The carboxyl­ate groups of the nitro­phthalate anion adopt a syn–anti bridging mode, linking adjacent Cd(II) cations and forming a polymeric chain running along the a axis. Weak intra- and inter­molecular C—H⋯O hydrogen bonding is present in the crystal structure.