Bis[(dihydrogen pyrophosphatoκ-2 O,O′)(2,2′: 6′,2″-terpyridine-κ3 N,N′,N″)copper(II) ] 4.5-hydrate

Abstract

The title copper complex, [Cu(H2P2O 7)(C15H11N3)]2·4. 5H2O, consists of two very similar independent Cu(Tpy)H 2P2O7 monomeric units (Tpy is 2,2′:6′,2″-terpyridine) plus four and a half water mol-ecules of hydration, some of which are disordered. Tpy units bind through the usual triple bite via their N atoms, and the H2P2O7 2- anions coordinate through two O atoms from two different phosphate units. Each independent CuN3O2 chromophore can be described as a slightly deformed square pyramid, with one of them having a sixth, semicoordinated, O atom from a centrosymmetrically related CuN 3O2 unit in a weakly bound second apical position suggesting an octa-hedral environment for the cation and weak dimerization of the molecule. The two independent complex molecules are connected via two strong O - H⋯O inter-actions between the phosphate groups to form hydrogen-bonded dinuclear units, further linked into [111] columns, resulting in a very complex three-dimensional supra-molecular structure through a variety of classical and nonclassical hydrogen bonds, as well as π-π interactions. © 2011 International Union of Crystallography.