Assembly of Polyoxometalate-Based Hybrids with Different Helical Channels upon Subtle Ligand Variation

Self-assembly of multiple components into well-defined and predictable structures remains one of the foremost challenges in chemistry. Here, upon subtle ligand variation, we reported on the assembly of three new polyoxometalate-based organic–inorganic hybrid compounds with different helical channel, [Ag3(H2pyttz-I)2]­[PMo12O40] (1), [Ag6(H2pyttz-II)4]­[CoW12O40]·2H2O (2), and [Ag7(Hpyttz-II)3(H2pyttz-II)]­[GeW12O40]·7H2O (3) (H2pyttz-I/II = 4-/3-pyrid-5-(1H-1,2,4-triazol-3-yl)-1,2,4-triazolyl, POM = polyoxometalates). X-ray diffraction analysis shows that compound 1 is constructed by “butterfly-like” Ag5(H2pyttz-I)2 subunits and POMs clusters, which are assembled into close helical channels impregnated with the components selves. Both compounds 2 and 3 are constructed by “paddle-wheel like” Ag4(H2pyttz-II)4 motifs and POMs clusters, which bring into being the larger helical channels (10.5% and 12.5% of the cell volume, respectively). Note that the only difference in compounds 2 and 3 is that the former contains 1D metal–organic chain structure, and the latter contains 2D metal–organic layer structure. In addition, the photocatalytic degradation of RhB by these compounds was also investigated

Synthesis and crystal structure of a two-dimensional CoII coordination polymer: poly[(μ3-3-carboxybenzoato)[μ2-5-(pyridin-4-yl)-1H,2′H-3,3′-bi[1,2,4-triazole]]cobalt(II)]

In the title compound, [Co(C8H5O4)(C9H6N7)]n, the divalent CoII atom is six-coordinated to three N atoms from two symmetrical 5-(pyridin-4-yl)-1H,2′H-3,3′-bi[1,2,4-triazole] (H2pyttz) ligands and three O atoms from three symmetrical 3-carboxybenzoate (Hbdic) ligands, leading to a distorted {CoN3O3} octahedral coordination environment. Two CoII cations are linked by four bridging carboxylate groups to generate a dinuclear [Co2(CO2)4] unit. The dinuclear units are further connected into a chain along [010] via the Hbdic ligands. The other infinite chain, along [100], is formed through the H2pyttz ligands. Finally, the two kinds of chains are cross-linked, by sharing the CoII cations, into a two-dimensional network. In the crystal, adjacent layers are further linked by O—H...N hydrogen bonds into a three-dimensional framework