Lanthanide perchlorate complexes with 1,4-bis(phenylsulfinyl)butane: structures and luminescent properties

Abstract

Five representative lanthanide coordination compounds with a disulfoxide ligand [L = 1,4-bis(phenylsulfinyl)butane], [Ln(L)₄](ClO₄)₃ (Ln = La, 1; Eu, 2; Gd, 3; Tb, 4; Yb, 5), have been synthesized and structurally characterized by single-crystal X-ray diffraction. These compounds have isostructural mononuclear structures, in which the ligand L coordinates to the metal ions through O donors in chelating coordination mode. The luminescence studies of 2 and 4 in the solid state and solution exhibit the usual metal-centred emission spectra arising from ligand-to-metal energy transfer, and their intensity and lifetimes are increased compared to those of previously reported analogous complexes {[Ln(L)₂(DMF)₄](ClO₄)₃·nH₂O}_∝ (Ln = Eu, n = 4, 6; Ln = Tb, n = 3, 7). The stability of these complexes in solution was also investigated.