Aqua-(4,4'-bipyridine-κN)bis-(1,4-dioxo-1,4-dihydronaphthalen-2-olato-κO,O)zinc 4,4'-bipyridine mono-solvate dihydrate.

The reaction of 2-hy-droxy-1,4-naphtho-quinone and 4,4'-bipyridine with zinc acetate produced the title compound, [Zn(C(10)H(5)O(3))(2)(C(10)H(8)N(2))(H(2)O)]·C(10)H(8)N(2)·2H(2)O. The bond lengths and angles around the metal atom indicate a deviation from octa-hedral geometry. The two naphtho-quinone ligands coordinate in a cis fashion, with the 4,4'-bipyridine ligand and the water mol-ecules completing the coordination sphere of the metal atom. The asymmetric unit contains also one free 4,4'-bipyridine mol-ecule and two uncoordinated water mol-ecules. These mol-ecules make contacts with the complex through O-H⋯N and O-H⋯O hydrogen bonds, creating a layer two-dimensional network parallel to (121).