Novel POMs-based Compounds With Helical Feature: Syntheses, Structures And Properties Study

Objective This paper attemped the synergistic effect of V-shaped organic N-donorligand, metal ions and POMs on the structures of novel POMs-based compounds withhelical feature. Programmable assembled POMs-based hybrids on molecularmechanism and investigated the relations between structures and activities.Methods POMs-based compounds with helical feature were hydrothermallysynthesized and characterized by routine methods (IR, ES and XPRD) and single-crystalX-ray crystallography. The photocatalytic properties were monitored by UV. In addition,theantibacterialactivitiesofthecomplexesweretested by thepaperdiscmethod.Results We systematically synthesis six kinds of POMs-based compounds withhelical feature, namely:Na[Ag6(pyttz)2(H2O)][PMo12O40](1);K[Ag14(pyttz)4(H2O)2][PW12O40]2·(OH)·5H2O (2);K[Ag14(pyttz)4(H2O)4][HSiW12O40]2·H2O (3);H2[Ag3(Hpyttz-I)2][PMo12O40](4);H2[Ag6(Hpyttz-II)2(H2pyttz-II)2][CoW12O40]·4H2O (5);[Ag7(Hpyttz-II)2(H2pyttz-II)2][GeW12O40]·(OH)·6H2O (6).We investigated the photocatalytic properties of compounds at the precence ofRhodamine-B (RhB). Compounds1,2,3,4and6displayed high photocatalytic properties incomparison with (NBu4)n[XM12O40]. There is no evidence shows that [CoW12O40]6-possesses of photocatalytic property. Therefore,[CoW12O40]6-can not transfer thephotocatalytic property into whole structure of compound5. In addition, we obtained theantibacterialdiameter bytheantimicrobialexperimentofsixkindsof compounds.Conclusion Six novel POMs-based compounds with helical feature with V-shapedorganic N-donor ligand and metal ions have been synthesized under hydrothermalconditions. The influences of the coordination modes of POM species, ligand isomers andmetal ions on the structures of the compounds have been discussed. The antibacterialexperiments exhibit that compounds have high antibacterial activity for E. coli and S. aureus.And reveal that the antibacterial activities transtered into structures of compounds and retained as well as their components. Since the POMs prossess photocatalytic properties inthe aquatic solution of dyes, compounds1,2,3,4and6may be good candidates forphotocatalyticcompositematerials.