Cobalt(II) and zinc(II)-coordination polymers constructed from ether-linked tetracarboxylic acid and isomeric bis(imidazole) linkers: luminescence-based Fe(m) detection in aqueous media

摘要

Four Co(II) and Zn(II)-coordination polymers, formulated as {{Co-2(mu(4)-L)(mu-mbix)(2)center dot 2H(2)O), (1), {[Co-2(mu(4)-L)(mu-pbix)(2)center dot 4H(2)O) n (2), {[Zn-2(mu(4)-L)(mu-mbix)(2)center dot 2H(2)O)(n) (3) and {[Zn-2(mu(4)-L(mu-pbix)(2)]center dot 4H(2)O)(n) (4) (H4L: (E)-5,5'-(but-2-ene-1,4-diylbis(oxy))diisophthalic acid, mbix: 1,3-bis((imidazol-1-yl)methyl)benzene and pbix: 1,4-bis((imidazol-1-yl)methyl)benzene), were synthesized and characterized by elemental analysis, IR spectroscopy and single crystal X-ray diffraction techniques. The single crystal X-ray diffraction analyses reveal that 1 and 3 display a 2D structure with a kgm topology with a point symbol of 3(2).6(2).7(2), while 2 and 4 exhibit 3D frameworks with a new topology with a point symbol of (8(6)). The detection ability of 3 which showed high luminesce intensity towards Fe3+ ions was investigated and compound 3 exhibited sensitive and selective detection towards Fe3+ ions in the presence of other competing agents with a detection limit of 3.23 ppm. Moreover, the topological and thermal properties of the compounds were also studied.