Bis[tris(ethylenediamine-κ2N,N′)cobalt(III)] octakis-μ-3-oxido-hexadeca-μ2-oxido-tetradecaoxido-μ12-tetraoxosilicato-octamolybdenum(VI)hexavanadium(IV,V) hexahydrate

Abstract

The title compound, [Co(C2H8N2)3]2[SiMo8V4O40(VO)2]·6H2O, was prepared under hydrothermal conditions. The asymmetric unit consists of a transition metal complex [Co(en)3]3+ cation (en is ethylenediamine), one half of an [SiMo8V4O40(VO)2]6− heteropolyanion, two solvent water molecules in general positions and two half-molecules of water located on a mirror plane. In the complex cation, the Co3+ ion is in a distorted octahedral coordination environment formed by six N atoms of the three chelating en ligands. One of the en ligands exhibits disorder of its aliphatic chain over two sets of sites of equal occupancy. The [SiMo8V4O40(VO)2]6− heteropolyanion is a four-electron reduced bivanadyl-capped α-Keggin-type molybdenum–vanadium–oxide cluster. In the crystal, it is located on a mirror plane, which results in disorder of the central tetrahedral SiO4 group: the O atoms of this group occupy two sets of sites related by a mirror plane. Furthermore, all of the eight μ2-oxide groups are also disordered over two sets of sites with equal occupancy. There are extensive intermolecular N—H...O hydrogen bonds between the complex cations and inorganic polyoxidoanions, leading to a three-dimensional supramolecular network.