1-D and 2-D coordination polymers of lead(II) thiocyanate with substituted 2,2′-bipyridine ligand

Abstract

Two lead(II)-thiocyanato coordination polymers with 5,5′-dimethyl-2, 2′-bipyridine (5,5′-dm-2,2′-bpy) and 4,4′-dimethoxy-2, 2′-bipyridine (4,4′-dmo-2,2′-bpy) as chelating ligands were synthesized and characterized by elemental analysis, IR and 1H-NMR spectroscopy, thermal behavior, and X-ray crystallography. These complexes have formulas [Pb(5,5′-dm-2,2′-bpy)(NCS) 2] n (1) and [Pb(4,4′-dmo-2,2′-bpy)(NCS) 2] n (2). The coordination numbers of Pb II in 1 and 2 are four, PbN 4, with "stereo-chemically active" electron pairs and hemidirected coordination spheres. Considering PbS as weak bonds, 1 and 2 are 1- and 2-D coordination polymers, respectively. The supramolecular features in these complexes are guided/controlled by weak directional intermolecular interactions. © 2012 Taylor & Francis.