μ(3)-Dodeca­tungsto(V,VI)aluminato-κ(3) O:O′:O′′-tris­[aqua­bis­(ethyl­ene­diamine-κ(2) N,N′)copper(II)]

The title compound, [AlCu(3)W(12)O(40)(C(2)H(8)N(2))(6)(H(2)O)(3)], was prepared under hydro­thermal conditions. The Cu(2+) ion displays an elongated octa­hedral geometry defined by one bridging O atom from the polyoxidoanion and a coordinated water mol­ecule in axial positions and four N atoms of the two chelating ethyl­enediamine (en) ligands in equatorial positions. The one-electron reduced [AlW(12)O(40)](6−) anion coordinates three [Cu(en)(H(2)O)](2+) fragments, generating a neutral tri-supported Keggin-type polyoxidometalate (POM). This tri-supported POM is located in a special position of [Image: see text] symmetry and therefore O atoms from the central AlO(4) tetra­hedron are disordered over two sets of sites. Disorder is also observed for three other bridging O atoms of the POM. In the crystal, mol­ecules are connected via N—H⋯O and O—H⋯O hydrogen bonds, forming a three-dimensional framework.