Solid state coordination chemistry: temperature dependence of the crystal chemistry of the oxovanadium-phenylphosphonate-copper(II)-2,2′-bipyridine system. Crystal structures of the one-dimensional [{Cu(bpy)}VO2(O3PC6H5)(HO3PC6H5)], [{Cu3(bpy)3(H2O)}V4O

The temperature dependence of the hydrothermal chemistry of the oxovanadium-phenylphosphonate/copper(II)-bipyridine system has been investigated. Reactions of identical compositions of CuSO4⋅5H2O, bipyridine, C6H5PO3H2 and Na3VO4 in H2O yielded [{Cu(bpy)}VO2(O3PC6H5)(HOC6H5)] (1), [{Cu3(bpy)3(H2O)}V4O9(O3PC6H5)4]⋅3.9H2O (2⋅3.9H2O) and [{Cu(bpy)}VO(O3PC6H5)2] (4) at 120 °C, 150 °C and 180-230 °C, respectively. Furthermore, variations in stoichiometry at 150 °C provided yet a fourth one-dimensional phase [{Cu(bpy)}2V3O6(O3PC6H5)3(HO3PC6H5)] (3). Substitution of a methyl substituent for the phenyl group yielded another one-dimensional material [{Cu(bpy)}V2O4(O3PCH3)2⋅H2O (5⋅H2O). The structural chemistry is discussed in terms of the polyhedral variability of vanadium oxides, the tendency of oxovanadium polyhedra to form oligomeric arrays, the variable modes of polyhedral connectivity associated with vanadium square pyramids and phosphorus tetrahedra and the steric influences of the copper(II)-bpy subunit.