Poly[[tris(di-2-pyridylamine)tris(μ-5-sulfonatosalicylato)tricopper(II)] trihydrate]

In the title compound, [Cu-3(C10H9N3)(3)(C7H3O6S)(2)].3H(2)O, [Cu-3(ssal)(2)(dpa)(3)] units (dpa is 2,2'-dipyridylamine and ssal is 5-sulfonatosalicylate) are found, which consist of one crystallographically independent ssal anion, and two each of crystallographically independent dpa ligands and Cu atoms, the unit lying on a twofold rotation axis. One Cu atom is four-coordinated by one dpa ligand and one ssal anion within a square-planar geometry, whereas the second Cu atom is coordinated by one dpa ligand and two ssal anions which are related by symmetry. The first Cu atom has one longer contact to one O atom of a symmetry-related sulfonate group and is, therefore, five-coordinated within a distorted square-pyramidal coordination. The [Cu-3(ssal)(2)(dpa)(3)] units are connected via the sulfonate groups into layers which are parallel to the ab plane. These layers are further connected by O-H...O and N-H...O hydrogen bonding via the water molecules.