New metal–organic architectures of cobalt(II), nickel(II) and zinc(II) with tripodal ligand 5-(1H-imidazol-4-ylmethyl)aminoisophthalic acid

Four new coordination polymers {[Ni(HL)(H2O)]·H2O}n (1), {[Co(HL)(H2O)]·H2O}n (2), {[Co(HL)]·4H2O}n (3) and {[Zn(HL)]·2H2O·0.5C2H5OH}n (4) [H3L = 5-(1H-imidazol-4-ylmethyl)aminoisophthalic acid] have been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction analyses. Complexes 1 and 2 display (3, 3)-connected 2D network with (4, 82) topology. While 3 and 4 exhibit a binodal (3, 6)-connected 2D network with a Schläfli symbol (43)2(46, 66, 83). The complexes 1–4 show remarkable thermal stability and 4 exhibits blue fluorescence with maximum emission at 413 nm upon excitation at 362 nm in the solid state at room temperature. In addition, the magnetic measurements of 3 indicate that there are antiferromagnetic interactions between the neighboring Co(II) centers.

Four novel coordination polymers with (3, 3)- and (3, 6)-connected 2D network structures have been synthesized by reactions of new imidazol- and carboxylate-containing ligand with Ni(II), Co(II) and Zn(II) salts under hydrothermal conditions. The thermal stability, luminescent, and magnetic properties of the complexes are investigated.Figure optionsDownload as PowerPoint slide