The synthesis and crystal structure of vanadium complexes: [V^IVO₂(phen)₂]·6H₂O and [2,2′-(bipy)₂ V^VO₂] (H₂BO₃)·3H₂O

The organic-inorganic hybrid materials vanadium oxide [V^IVO₂(phen)₂]·6H₂O (1) and [(2,2′-bipy)₂V^VO₂] (H₂BO₃)·3H₂O (2) have been conventional and hydrothermal synthesized and characterized by single crystal X-ray diffraction, elemental analyses, respectively. Although the method and the ligand had been used in the syntheses of the compounds (1) and (2) are different, they almost possess similar structure. They all exhibit the distorted octahedral [VO₂N₄] unit with organonitrogen donors of the phen and 2,2′-bipy ligands, respectively, which coordinated directly to the vanadium oxide framework. And they are both non-mixed-valence complexes. But the compound (1) is isolated, and the compound (2) consists of a cation of [(2,2′- bipy)₂V^VO₂]⁺ and an anion of (H₂BO₃)^-. So the valence of vanadium of (1) and (2) are tetravalence and pentavalence, respectively. Meanwhile it is noteworthy that π-π stacking interaction between adjacent phen and 2,2′-bipy groups in compounds 1 and 2 also play a significant role in stabilization of the structure. Thus, the structure of [V^IVO₂(phen)₂]′6H₂O and [(2,2′-bipy)₂V^VO₂] (H₂BO₃)·3H₂O are both further extended into interesting three-dimensional supramolecular. Crystal data: (1) Triclinic, P1, a = 8.481(4), b = 12.097(5), and c = 14.607(6) Å, α = 66.32(2), β = 82.97(3), and γ = 82.59(4)°, V = 1357.0(10) ų, Z = 2, R₁ = 0.0685, wR₂ = 0.1522. (2) Triclinic, P1, a = 6.643(13), b = 11.794(2), and c = 14.822(3) Å, α = 101.39(3), β = 101.59(3), and γ = 97.15(3)°, V = 1098.8(4) ų, Z = 2, R₁ = 0.0736, wR₂ = 0.1998.