Self-Assembly of a Series of Extended Architectures Based on Polyoxometalate Clusters and Silver Coordination Complexes

Three unusual compounds based on polyoxometalate building blocks, [(H<sub>2</sub>O)<sub>5</sub>Na<sub>2</sub>(C<sub>6</sub>NO<sub>2</sub>H<sub>4</sub>)(C<sub>6</sub>NO<sub>2</sub>H<sub>5</sub>)<sub>3</sub>Ag<sub>2</sub>][Ag<sub>2</sub>IMo<sub>6</sub>O<sub>24</sub>(H<sub>2</sub>O)<sub>4</sub>]·6.25H<sub>2</sub>O (<b>1</b>), [(H<sub>2</sub>O)<sub>4</sub>Na<sub>2</sub>(C<sub>6</sub>NO<sub>2</sub>H<sub>5</sub>)<sub>6</sub>Ag<sub>3</sub>][IMo<sub>6</sub>O<sub>24</sub>]·6H<sub>2</sub>O (<b>2</b>), and (C<sub>6</sub>NO<sub>2</sub>H<sub>6</sub>)<sub>2</sub>[(C<sub>6</sub>NO<sub>2</sub>H<sub>5</sub>)<sub>2</sub>Ag][Cr(OH)<sub>6</sub>Mo<sub>6</sub>O<sub>18</sub>]·4H<sub>2</sub>O (<b>3</b>), have been synthesized and characterized by elemental analysis; IR, XPS, and ESR spectroscopy; TG analysis; and single-crystal X-ray diffraction. Compound <b>1</b> is constructed from the cationic two-dimensional (2D) coordination polymer sheets which are constituted of [(H<sub>2</sub>O)<sub>5</sub>Na<sub>2</sub>(C<sub>6</sub>NO<sub>2</sub>H<sub>4</sub>)(C<sub>6</sub>NO<sub>2</sub>H<sub>5</sub>)<sub>3</sub>Ag<sub>2</sub>]<sup>3+</sup> and anionic [Ag<sub>2</sub>IMo<sub>6</sub>O<sub>24</sub>(H<sub>2</sub>O)<sub>4</sub>]<sup>3-</sup> chains as pillars, forming a three-dimensional (3D) supramolecular framework via weak Ag−O interactions. Compound <b>2</b> is composed of the well-defined [IMo<sub>6</sub>O<sub>24</sub>]<sup>5-</sup> building blocks, which are linked through trinuclear Ag-pyridine-3-carboxylic acid, [(C<sub>6</sub>NO<sub>2</sub>H<sub>5</sub>)<sub>6</sub>Ag<sub>3</sub>]<sup>3+</sup>, fragments into a one-dimensional (1D) hybrid chain; adjacent chains are further connected by sodium cations to yield a novel 2D network. Compound <b>3</b> has a 1D chainlike structure constructed from [Cr(OH)<sub>6</sub>Mo<sub>6</sub>O<sub>18</sub>]<sup>3-</sup> building blocks and Ag-pyridine-4-carboxylic acid coordination units. The crystal data for these compounds are the following:  <b>1</b>, triclinic, <i>P</i>1̄, <i>a</i> = 13.280(3) Å, <i>b</i> = 13.641(3) Å, <i>c</i> = 16.356(3) Å, α = 89.68(3)°, β = 88.31(3)°, γ = 75.87(3)°, <i>Z</i> = 2; <b>2</b>, triclinic, <i>P</i>1̄, <i>a</i> = 11.978(2) Å, <i>b</i> = 12.008(2) Å, <i>c</i> = 13.607(3) Å, α = 116.14(3)°, β = 108.85(3)°, γ = 93.86(3)°, <i>Z</i> = 1; <b>3</b>, triclinic, <i>P</i>1̄, <i>a</i> = 10.458(2) Å, <i>b</i> = 10.644(2) Å, <i>c</i> = 12.295(3) Å, α = 97.40(3)°, β = 112.38(3)°, γ = 113.59(3)°, <i>Z</i> = 1.