Structural variations and photoluminescent properties of a series of metal-organic frameworks constructed from 5-(4-carboxybenzoylamino)-isophthalic acid

• A tricarboxylate ligand whose coordinating functionalities are not symmetry equivalent is employed to construct MOFs.
• Complex 2 features an interesting 2D→3D catenation architecture containing helical chains.
• Complex 3 feature chain-like structure containing free – COOH group, which may confer unique functionality.
• Photoluminescent properties and thermal behaviors for 1–5 have been reported.

Five new metal-organic frameworks (MOFs) with 5-(4-carboxybenzoylamino)-isophthalic acid (H3L), namely, [Cd9L6(DMA)6]·4DMA (1), [Cd3L2(H2O)9]·4H2O (2), [LaL(H2O)4]·2H2O (3), [CeL(H2O)4]·H2O (4) and [Tb(HL)(H2L)(H2O)3]·5H2O (5) (DMA=N,N-dimethylacetamide), have been synthesized. Complex 1 shows a three-dimensional architecture generated from linkage of Cd–O chains via L3− ligands. Minor variations in synthetic conditions of 1 afforded 2, which features an interesting 2D→3D catenation architecture containing helical chains. Complexes 3 and 4 are isostructural and each feature a two-dimensional architecture constructed from the linkage of L3− with Ln3+. Complex 5 displays a chain-like structure, of which the most interesting feature is the existence of free carboxylic acid (–COOH) group which may confer unique functionality. Moreover, the investigations of the thermal stability, powder X-ray diffractions and solid-state photoluminescent properties for these crystalline materials have been carried out.

Graphical AbstractSolvothermal reactions of tricarboxylate ligand H3L with Cd2+/Ln3+ has yielded a series of new MOFs containing interesting structural motifs.Figure optionsDownload as PowerPoint slide