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] x 6.25H2O (1), (H2O)4Na2(C6NO2H5)6Ag3]IMo6O24] x 6H2O (2), and (C6NO2H6)2(C6NO2H5)2Ag]Cr(OH)6Mo6O18] x 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, P1, a = 13.280(3) A, b = 13.641(3) A, c = 16.356(3) A, alpha = 89.68(3) degrees, beta = 88.31(3) degrees, gamma = 75.87(3) degrees, Z = 2; 2, triclinic, P1, a = 11.978(2) A, b = 12.008(2) A, c = 13.607(3) A, alpha = 116.14(3) degrees, beta = 108.85(3) degrees, gamma = 93.86(3) degrees, Z = 1; 3, triclinic, P1, a = 10.458(2) A, b = 10.644(2) A, c = 12.295(3) A, alpha = 97.40(3) degrees, beta = 112.38(3) degrees, gamma = 113.59(3) degrees, Z = 1.