Assembly and Properties of Four New Metal–Organic Complexes Based on 1,4-Naphthalenedicarboxylate: Effect of Four Bis-pyridyl-bis-amide Ligands with Diverse Spacers in the Structures

Abstract

Four new complexes based on 1,4-naphthalenedicarboxylic acid (1,4-H 2 NDC) and four bis-pyridyl-bis-amide ligands with various spacers (3-bpye ¼ N,N 0 -bis(3-pyridinecarboxamide)-1,2-ethane; 3-bpfp ¼ bis(3-pyridylformyl)piperazine; 3-bpcd ¼ N,N 0 -bis(pyridin-3-yl)cyclohexane-1,4-dicarboxamide; and 3-bpcb (4), have been hydrothermally synthesized. Complex 1 is a 3D coordination network and represents an 8-connected {4 20 .6 8 } topology. Complex 2 shows a 2-fold interpenetrating 3D architecture with a 6-connected {4 12 .6 3 } topology. Complexes 3 and 4 possess similar 2D sql layers with the {4 4 .6 2 } topology, but the coordination modes of 1,4-NDC ligands and the conformations of the two bis-pyridyl-bis-amide ligands are different. The adjacent layers for 3 and 4 are further linked by hydrogen bonding interactions to form 3D supramolecular networks. The successful assemblies of complexes 1-4 imply that by using the different bis-pyridyl-bis-amide ligands with diverse spacers can produce diverse metal-organic networks. Furthermore, the fluorescence and photocatalytic properties of complexes 1-4 have been investigated.