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)

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 thef-block metal (Nd or Eu). Compounds 2 and 3 exhibited the emission quenching of the Ln(3+) ion, which probably arises from the Ln(3+) -> Ni2+ energy transfer. (C) 2016 Elsevier Ltd. All rights reserved.