Supramolecular chain-like polymers based on Ln(III) aqua complexes and cucurbit[6]uril

Abstract

Five new supramolecular coordination polymers based on cucurbit[6]uril (CB[6]) and mononuclear lanthanide (III) ions were synthesized and structurally characterized by single-crystal X-ray diffraction. They are [{Nd(H2O)5(NO3)}2(CB[6])](NO3)4·7H2O (1), [Gd(H2O)3(dmf)(CB[6])(NO3)](NO3)2·5H2O (2), [Gd(H2O)4(CB[6])(NO3)](NO3)2·7H2O (3), [Gd(H2O)3(dmf)(CB[6])(HCOO)](NO3)2·6H2O (4), and [{Ho(H2O)6}2(CB[6])]Cl6·6H2O (5). The crystal structures of complexes 1–5 showed that packing of mononuclear ions and macrocycles gives rise to supramolecular chain-like polymers. The complexes were characterized by TG, elemental analysis, and IR spectroscopy. The fluorescent properties for 1, 3 and 5 were analyzed. The magnetic properties of 2 and 4 were also studied.