Solid state coordination chemistry of oxovanadates: hydrothermal syntheses and structures of two novel copper vanadate ribbons, β-[Cu(2,2′-bipyridine)V2O6] and β-[Cu(2,2′∶6′,2″-terpyridine)V2O6]

The hydrothermal reaction of CuSO4·5H2O, Na3VO4, methylphosphonic acid, 2,2′-bipyridine, and H2O in the mole ratio 1.22 ∶ 1.30 ∶ 3.63 ∶ 1.00 ∶ 2250 at 150 °C for 43 h yielded β-[Cu(bpy)V2O6] (1). The structure of 1 is a one-dimensional ribbon constructed of {V6O18}6− clusters linked by a binuclear subunit of edge sharing {Cu(bpy)O3} square pyramids. Similarly, the reaction of Cu2O, Na3VO4, 2,2′∶6′,2″-terpyridine, selenous acid, and water, in a mole ratio 1.52 ∶ 1.00 ∶ 2.02 ∶ 9.31 ∶ 2130 at 200 °C for 67.5 h yielded β-[Cu(tpy)V2O6] (2). The structure of 2 is comprised of an undulating chain of corner sharing vanadium oxide tetrahedra, with {Cu(tpy)}2+ subunits spanning the adjacent crests and troughs.