Two-dimensional oxides constructed from octamolybdate clusters and Mn+/tetrapyridylpyrazine subunits (M = Co, Ni: n = 2; M = Cu: n = 1)

The hydrothermal reactions of MoO3, tetra-2-pyridylpyrazine (tpyprz) and M(CH3CO2)2 · 2H2O (M = Co, Ni) yielded the two-dimensional oxides [M2(tpyprz)(H2O)2Mo8O26] · x H2O [M = Co, x = 1.8 (1); M = Ni, x = 0.6 (2)]. However, the reaction of (NH4)6Mo7O24 · 4H2O, tpyprz and Cu(CH3CO2)2 · H2O produced [{Cu2(tpyprz)}2Mo8O26] · 2H2O (3 · 2H2O). The isomorphous structures of 1 and 2 are constructed from View the MathML sourceα-Mo8O264- clusters linked through {M2(tpyprz)(H2O)2}4+ subunits into two-dimensional networks. While the structure of 3 is also two-dimensional, the molybdate building block is present as the δ-isomer and the secondary-metal/ligand component consists of a one-dimensional View the MathML source{Cu2(tpyprz)}n2n+ chain. The structure of 3 is compared to that of the previously reported three-dimensional material [{Cu2(tpyprz)}2Mo8O26] · 7H2O which contains View the MathML sourceζ-Mo8O264-clusters and structurally distinct View the MathML source{Cu2(tpyprz)}n2n+ chains.