2-D coordination polymers of copper and cobalt with 3,4-pyridinedicarboxylic acid: synthesis, characterization, and crystal structures

Two new complexes involving 3,4-pyridinedicarboxylic acid (3,4-H(2)pdc), copper(II) and cobalt(II) complexes, {[Cu(3,4-Hpdc)(2)(H2O)(2)]center dot 2dmso}(n) (1) and {[Co(3,4-Hpdc)(2)(H2O)(2)]center dot 2H(2)O center dot 2dmso}(n) (2) (dmso=dimethylsulfoxide), have been synthesized by the diffusion method and characterized by elemental analysis, IR spectroscopy, thermal analysis, powder and single-crystal X-ray diffraction analysis, and electron paramagnetic resonance (EPR). In both compounds, the metal coordination sphere is composed of a trans-MO4N2 core and adopts a distorted octahedral geometry in accordance with X-ray diffraction and EPR results. 3,4-Hpdc(-) ligands bridge the metal centers giving two-dimensional (2-D) coordination polymers with four-connected uninodal nets of (4,4) topology.