Syntheses, crystal structures, properties of zinc(II) and cadmium(II) coordination polymers based on a novel asymmetric semi-rigid multicarboxylate ligand

Abstract

Abstract A series of new metal coordination polymers constructed from a novel asymmetric semi-rigid aromatic carboxylate ligand, namely, {[M2L·5H2O]∙2H2O}n ((M = Zn, and Cd for 1 and 2, respectively), {[Zn2(L)(bipy)(H2O)2]·3H2O}n (3), and {[Zn(HL)(Habpt)(H2O)2]2·5H2O}n (4) (H4L = 4-((3,5-dicarboxyphenyl)carbamoyl)phthalic acid; bipy = 4,4′-bipyridine; abpt = 4-amino-3,5-bis(4-pyridyl)-1,2,4-triazole), have been hydrothermally synthesized and characterized by elemental analysis, infrared spectra, and single-crystal X-ray diffraction. Both compounds 1 and 2 present three-dimensional coordination networks. Compound 3 forms a two-dimensional layer structure whereas 4 displays a one-dimensional (1D) chain structure built from both Habpt ligand and HL3− ligand, which further extend into three-dimensional network via hydrogen bonds. The versatile structures of the title polymers indicate that structural diversity may be influenced by various factors, such as the coordination mode of ligands, the nature of metal nodes and the kind of ancillary ligand. Additionally, the photoluminescence of 1–4 were also investigated.