title: Synthesis, structure and characterization of a helical seven-coordinated pyridine-2,6-dicarboxylate-bridged cadmium(II) complex.
abstract: [Cd(C7H3NO4)(H2O)1.5]n or [Cd(2,6-pydc)(H2O)1.5]n, (1) (2,6-pydc = pyridine-2,6-dicarboxylate) was obtained from the reaction of pyridine-2,6-dicarboxylic acid and 4-hydroxypyridine-2,6-dicarboxylic acid with cadmium(II) nitrate tetrahydrate in the presence of piperazine and characterized by elemental analysis, IR spectra and X-ray single crystal diffraction. Complex (1) is a novel carboxylate-bridged one-dimensional pincer-shaped helical chain of cadmium(II) polymer. Each Cd atom is seven-coordinate and exhibits an approximately pentagonal-bipyramidal CdNO6 coordination geometry. The metal fragments are linked via the central four-membered Cd2O2 ring and the structural analysis showed that 4-hydroxypyridine-2,6-dicarboxylic acid and piperazine do not appear in the structure.
authors.affiliation: Department of Chemistry, Qom Branch, Islamic Azad University, Qom, Iran. sharif44m@yahoo.com
authors.forename: Mahboubeh A
authors.initials: MA
authors.lastname: Sharif
authors.forename: Gholam Reza
authors.initials: GR
authors.lastname: Najafi