Solid-state coordination chemistry of molybdenum oxides with di-2-picolylamine (pca): The hydrothermal syntheses and structures of the molecular cluster [{Ni(pca)(H₂O)}₂Mo₈O₂₆], the two-dimensional [{Cu(pca)}₂Mo₈O₂₆], and the one-dimensional [{Cu₃(pca)₃MoO₄}Mo₈O ₂₆]

The hydrothermal reaction of di-2-picolylamine (pca), MoO₃ and NiSO₄·6H₂O yielded the bimetallic oxide cluster [{Ni(pca)(H₂O)}₂Mo₈O₂₆]· 2H₂O (1.2H₂O). Similarly, the reaction of pca, MoO₃ and CuSO₄·5H₂O produced the two-dimensional material [{Cu(pca)}₂Mo₈O₂₆] (2). The structure of 1 consists of β-{Mo₈O₂₆}^4- clusters, decorated with {Ni(pca)(H₂O)}²⁺ subunits, linked to terminal molybdenyl {Mo=O} moieties. The structure of 2 also contains β-{Mo₈O₂₆}^4- clusters as building blocks; however, in this instance, the {Cu(pca)}²⁺ subunits serve to bridge adjacent clusters into a two-dimensional network. The hydrothermal reaction of pca and CuSO₄·5H₂O with MoO₂ in place of MoO₃ produced [{Cu₃(pca)₃MoO₄}Mo₈O ₂₆]·2H₂O (3.2H₂O), a one-dimensional material, constructed from β-{Mo₈O₂₆}^4- clusters linked through unusual {Cu₃(pca)₃MoO₄}⁴⁺ subunits. Crystal data: C₁₂H₁₇N₃O₁₅Mo₄Ni (1.2H₂O): triclinic P1, a = 9.4024(5) Å, b = 10.9729(6) Å, c = 11.4183(6) Å, α = 102.710(1)°, β = 99.731(1)°, γ = 90.021(1)°, V = 1131.8(1) ų, Z = 2, D_calc = 2.596 g cm^-3; C₁₂H₁₃N₃O₁₃Mo₄Cu (2): monoclinic P2₁/n, a = 12.1547(4) Å, b = 12.5412(4) Å, c = 14.1160(4) Å, β = 92.746 (1)°, V = 2149.3(1) ų, Z = 4, D_calc = 2.638 g cm^-3; C₃₆H₄₃Cu₃ Mo₉N₉O₃₂ (3.2H₂O), monoclinic, P2₁/c, a = 17.9115(6) Å, b = 14.3637(5) Å, c = 22.6795(8) Å, β = 94.744(1)°, V = 5814.9(3) ų, Z = 4, D_calc = 2.476 g cm^-3.