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

Three unusual compounds based on polyoxometalate building blocks, [(H2O)5Na2(C6NO2H4)(C6NO2H5)3Ag2][Ag2IMo6O24(H2O)4]·6.25H2O (1), [(H2O)4Na2(C6NO2H5)6Ag3][IMo6O24]·6H2O (2), and (C6NO2H6)2[(C6NO2H5)2Ag][Cr(OH)6Mo6O18]·4H2O (3), have been synthesized and characterized by elemental analysis; IR, XPS, and ESR spectroscopy; TG analysis; and single-crystal X-ray diffraction. Compound 1 is constructed from the cationic two-dimensional (2D) coordination polymer sheets which are constituted of [(H2O)5Na2(C6NO2H4)(C6NO2H5)3Ag2]3+ and anionic [Ag2IMo6O24(H2O)4]3- chains as pillars, forming a three-dimensional (3D) supramolecular framework via weak Ag−O interactions. Compound 2 is composed of the well-defined [IMo6O24]5- building blocks, which are linked through trinuclear Ag-pyridine-3-carboxylic acid, [(C6NO2H5)6Ag3]3+, fragments into a one-dimensional (1D) hybrid chain; adjacent chains are further connected by sodium cations to yield a novel 2D network. Compound 3 has a 1D chainlike structure constructed from [Cr(OH)6Mo6O18]3- building blocks and Ag-pyridine-4-carboxylic acid coordination units. The crystal data for these compounds are the following:  1, triclinic, P1̄, a = 13.280(3) Å, b = 13.641(3) Å, c = 16.356(3) Å, α = 89.68(3)°, β = 88.31(3)°, γ = 75.87(3)°, Z = 2; 2, triclinic, P1̄, a = 11.978(2) Å, b = 12.008(2) Å, c = 13.607(3) Å, α = 116.14(3)°, β = 108.85(3)°, γ = 93.86(3)°, Z = 1; 3, triclinic, P1̄, a = 10.458(2) Å, b = 10.644(2) Å, c = 12.295(3) Å, α = 97.40(3)°, β = 112.38(3)°, γ = 113.59(3)°, Z = 1.