A series of 2D lanthanide (III) coordination polymers constructed from 2-(pyridin-3-yl)-1H-imidazole-4,5-dicarboxylate

Reactions of 2-(pyridine-3-yl)-1H-4,5-imidazoledicarboxylic acid (H3PyIDC) with a series of Ln(III) ions affords ten coordination polymers, namely, {[Ln(H2PyIDC)(HPyIDC)(H2O)2]·H2O}n [Ln=Nd (1), Sm (2), Eu (3) and Gd (4)], {[Ln(HPyIDC)(H2O)3]·(H2PyIDC)·H2O}n [Ln=Gd (5), Tb (6), Dy (7), Ho (8) and Er (9)], and {[Y2(HPyIDC)2(H2O)5]·(bpy)·(NO3)2·3H2O}n (10) (bpy=4,4′-bipyridine). They exhibit three types of networks: complexes 1–4 are isomorphous coordination networks containing neutral 2D metal-organic layers, while complexes 5–9 are isomorphous, which consist of cationic metal-organic layers and anionic organic layers, and complex 10 is a 2D network built up from 4-connected HPyIDC2− anion and 4-connected Y(III) ions. In addition, thermogravimetric analyses and solid-state luminescent properties of the selected complexes are investigated. They exhibit intense, characteristic emissions in the visible region at room temperature.