Vanadium(IV) dimer complexes containing [V(o-C6H4OS)3]2− fragment and caged sodium ions

Triso-mercaptophenolato]vanadium(IV) dimer complexes (A)₂V(mp)₃NaLL']₂ (A = Ph₄P₊, H₂mp = o-mercaptophenol, L = MeCN, L'=EtOH, (1); L' = MeOH, (2)) were prepared by the reaction of anhydrous VC1₃, and Na₂mp in the molar ratio 1:3. Complex (3) (A = Et₄N⁺, L=L' = MeOH) was prepared by the reaction of VC1₃, Na₂mp and Li₂S in the molar ratio 1:2:1. The complexes were characterized by X-ray diffraction crystallography, infrared spectra, magnetic susceptibility, and cyclic voltammetric measurements. Complex 2 crystallizes in the triclinic space group P1 with a=12.813(6), b = 14.199(4), c = 12.790(5) Å, α = 112.72(2), β = 104.24(4). γ = 88.68(4)°, V = 2073.6 ų, and Z=1. The structure was refined to R=0.058. Complex 3 crystallizes in the mono-clinic space group P2₁/n with a=12.359(3), b=17.452(6), c=14.829(13) Å, βequals;96.51(5)°, V=3177.8 ų, and Z=2. The final R factor is 0.067. Both of the anions of 2 and 3 contain two V(mp)₃]^2? fragments linked by sodium ions through the μ₃-O bridges with a crystallographic center of symmetry. The V(IV) atom is in a coordination environment intermediate between a trigonal prism and an ideal octahedron.