Two-dimensional 3d–4f coordination polymers based on compartment compounds: [NiLn(L)(NO3)2(4-pca)(H2O)] (Ln = Nd, Eu, Tb; H2L = 1,3-bis((3-methoxysalicylidene)amino)propane); 4-Hpca = pyridine-4-carboxylic acid)

Abstract

This paper describes the preparation and properties of Ni–Nd, Ni–Eu, and Ni–Tb coordination polymers, by using dinuclear 3d–4f compartment compounds as secondary building units. Under microwave-heating conditions in acetonitrile, two-dimensional 3d–4f coordination polymers, [NiLn(L)(NO3)2(4-pca)(H2O)] {Ln=Nd (1), Eu (2), Tb (3)}, were prepared from [NiLn(L)(NO3)(CH3CN)(H2O)4](NO3)2(H2O) and pyridine-4-carboxylic acid (4-Hpca). X-ray diffraction studies of polymers 1 and 2 clearly revealed that the pyridine terminal of the compartment ligand (L) is coordinated to the d-block metal (Ni) and the carboxylate terminal is coordinated the f-block metal (Nd or Eu). Compounds 2 and 3 exhibited the emission quenching of the Ln3+ ion, which probably arises from the Ln3+→Ni2+ energy transfer.