One- and Two-Dimensional Coordination Polymers Constructed from Bicapped Keggin Mixed Molybdenum−Vanadium Heteropolyoxoanions and Polynuclear Copper(I) Clusters Bridged by Asymmetrical Bipyridine (2,4‘-bipy and 2,3‘-bipy) Ligands

Two novel trimetallic coordination polymers containing bridging bicapped Keggin mixed Mo/V polyoxoanions and
asymmetrical aromatic amine bridging ligands 2,3‘-bipyridine (2,3‘-bipy) or 2,4‘-bipyridine (2,4‘-bipy), [CuI6(2,3‘-bipy)6(2,3‘-bipy-2‘-O)2][VIV2MoV5MoVI7O38(PO4)] [2,3‘-bipy-2‘-OH = 3-(pyridin-2-yl)pyridin-2-ol] (1) and [CuI5(2,4‘-bipy)6(OH)][PMoVI8VV3VIVO40(VIVO)2]·1.5H2O (2), have been prepared under hydrothermal conditions and structurally characterized by single-crystal X-ray
diffraction. Gillard type hydration for the 2,3‘-bipy ligand was observed during synthesis of 1, which happens on the 2‘-carbon atom
rather than on the α-carbon atom of the coordinated nitrogen atom in the 2,3‘-bipy ligand. Complex 1 is constructed from an
alternatively arranged bivanadyl capped α-Keggin polymolybdate anion [VIV2MoV5MoVI7O38(PO4)]4- and double 2,3‘-bipy ligand
bridged trinuclear copper(I) cluster [CuI3(2,3‘-bipy)3(2,3‘-bipy-2‘-O)]2+, forming a one-dimensional (1D) ribbon structure. The two-dimensional (2D) extended layer structure of 2 is composed of another type of bicapped Keggin mixed molybdenum−vanadium
polyoxoanion [PMoVI8VV3VIVO40(VIVO)2]4- and copper(I) coordination polymer cation chain [CuI5(2,4‘-bipy)6(OH)]4+; the latter
consists of a 2,4‘-bipy ligand bridged hexanuclear copper(I) cluster [CuI5(2,4‘-bipy)6]5+ linked by double hydroxyl groups.