Inorganic–organic hybrid materials: synthesis and crystal structures of the layered solids [{M(H2O)(2,2′-bipy)}V2O6] (M=Co, Ni)

Abstract

Two novel inorganic–organic hybrids [Co(H2O)(2,2′-bipy)V2O6] (1) and [Ni(H2O)(2,2′-bipy)V2O6] (2) have been prepared in 70–78% yields by the hydrothermal reactions of V2O5, LiOH·H2O, 2,2′-bipyridine (2,2′-bipy), MSO4·xH2O (M=Co, x=7, 1; M=Ni, x=6, 2), and H2O carried out in Teflon-lined autoclaves at 160 °C for 96 h. The new solids have been characterized by single crystal X-ray structure analyses, manganometric titration, elemental and thermogravimetric analysis, and IR spectroscopic studies. The isomorphous structures of 1–2 are comprised of {M/V/O} layers-perpendicular to the b-axis- composed of corner-sharing {VO4} tetrahedra and {CoN2O4} octahedra. The mixed-metal oxide layers contain [V2O62−]n motifs made up of corner-sharing {VO4} tetrahedra. The 2,2′-bipyridyl groups, bonded to the M centers in the layers, are projecting outward to occupy regions in between the successive metal oxide layers. Crystal data: 1, C10H10CoN2O7V2, orthorhombic space group Pca2(1),a=9.1870(4),b=10.5451(5),c=14.3487(6)Å, V=1390.07(11)Å3, Z=4, ρcalc=2.059Mgm−3, R1=0.0167; 2, C10H10NiN2O7V2, orthorhombic space group Pca2(1),a=9.1445(4),b=10.5076(5),c=14.3123(6)Å, V=1375.22(11)Å3, Z=4, ρcalc=2.081Mgm−3, R1=0.0214.