Synthesis, Structures, and Photoluminescence Properties of Five Novel Zinc(II) and Cadmium(II) Coordination Polymers based on Different Zwitterionic Pyridine Ligands

Abstract

A series of five new Zn II and Cd II mixed-ligand coordination polymers, namely, {[Zn(L 1 )(4,4Ј-bpy)]·(ClO 4 )·2H 2 O} (1), {[Zn(L 2 )(4,4Ј-bpy) 0.5 ]·(ClO 4 )} (2), {[Zn(L 3 )(4,4Ј-bpy)]·(NO 3 )·2H 2 O} (3), {[Cd(L 4 )(4,4Ј-bpy) 0.5 (NO 3 )]·5H 2 O} (4), and {[Zn(L 4 )(4,4Јbpy)]·Cl·H 2 O} (5) [4,4Ј-bpy = 4,4Ј-bipyridine, L 1 = 4-carboxy-1-(4carboxybenzyl)pyridin-1-ium chloride, L 2 = 3-carboxy-1-(4-carboxybenzyl)pyridin-1-ium chloride, L 3 = 4-carboxy-1-(3-carboxybenzyl)pyridin-1-ium chloride, and L 4 = 3-carboxy-1-(3-carboxybenzyl)pyridin-1-ium chloride], were obtained by the reactions of the 4,4Ј-bipyridine with four dicarboxylate zwitterionic pyridine ligands. Single-crystal X-ray structural analyses reveal that the five complexes demonstrate different molecular frameworks coming from various coordination modes and flexibilities of different dicarboxylate zwitterionic pyridine ligands and central metal atoms. Mononuclear

Crystal structure of a one-dimensional coordination polymer of gadolinium dibromoacetate with 4,4'-bipyridine

“…4,4'-Bipyridine may be one or two donor ligand, which gives different possibilities of coordination. Two nitrogen atoms opposing themselves and two independent pyridine rings with ability to rotation along C-C bond give chance to create coordination polymers [10][11][12][13][14]. The structure will depend on the size and coordination number of metal ion as well as the presence of other ligands.…”