1D, 2D and 3D cadmium(II) polymeric complexes with quinoline-4-carboxylato anion, quinazoline and 2,5-dimethylpyrazine

Artikel i vetenskaplig tidskrift, 2006

Three new cadmium(II) complexes, namely [Cd(Qux)2(H2O)]n (1), [Cd(Quz)2(N3)2]n (2) and [Cd(dmpz)(N3)2]n (3) (Qux = quinoline-4-carboxylato anion, Quz = quinazoline, dmpz = 2,5-dimethylpyrazine), have been synthesized and characterized by spectroscopic and crystallographic methods. The structure of 1 contains CdO6 slightly distorted octahedral geometry around the Cd(II) atoms, axialy coordinated to two bridging water molecules forming the 1D chain and four oxygen atoms from four different μ-O,O′-bridging caboxylato groups of (Qux) in the equatorial plane. The 1D chains are further held together through hydrogen bonds between the μ-aqua molecule and the meta non-coordinated nitrogen atom of the quinoline moiety. In complex 2, two quinazoline ligands are linked to the central Cd(II) ion in a trans position through the meta hetero nitrogen atom and di(EE), (μ1,3-N3) groups and show a two dimensional (2D) topology. In complex 3 the central cadmium(II) atom is simultaneously coordinated to di(EE), (μ1,3-N3) groups (N–Cd–N, 180.0°) forming a sheet structure in the bc plane and further bridging μ-N,N′-dimethylpyrazine ligand in the a-direction (N–Cd–N, 180.0°) giving rise to a 3D network structure. The IR spectra of the three complexes were measured and they confirm the X-ray structural data.