Novel Tungstovanadate Wells−Dawson Organic–Inorganic Heteropolyoxometalate Compound: Synthesis and Crystal Structure of [Cu2(2,2′-bipy)2(Inic)2(H2O)2][Y(Inic)2(H2O)5]H3[V2W18O62]·5.5H2O (Where 2,2′-bipy = 2,2′-Bipyridine, Inic = γ-Picolinic Acid)

A novel organic–inorganic heteropolyoxometalate compound [Cu2(2,2′-bipy)2(Inic)2(H2O)2][Y(Inic)2(H2O)5]H3[V2W18O62]·5.5H2O (1) was hydrothermally synthesized by reaction of Cu(CH3COO)2·4H2O, Y(NO3)3, V2O5, K9BW11O39, 2,2′-bipyridine, and γ-picolinic acid. The molecular asymmetric unit of 1 consists of one crystallographically independent heteropolyoxoanion [V2W18O62]6−, one dinuclear copper cation [Cu2(2,2′-bipy)2(Inic)2(H2O)2]2+, one nine-coordinated yttrium cation [Y(Inic)2(H2O)5]+, 5.5 water molecules of crystallization, and three protons based on charge balance. The polyoxoanion of 1 retains a classical Wells−Dawson structure. Unexpectedly, the Dawson-type anion with V atoms as heteroatoms has never been reported up to now.