Synthesis, crystal structure and characterization of ternary complexes of lanthanide(III) 3,5-di- tert-butyl-γ-resorcylate with substituted pyridine- N-oxide

Abstract

Twenty one ternary complexes of lanthanide with 3,5-di- tert-butyl-γ-resorcylic acid (L) and seven different substituted pyridine- N-oxides (L 1–7), with compositions of REL 3L 1–7 2· nH 2O (RE=Nd, Gd, Er; L 1=4-picoline- N-oxide; L 2=4-phenyl-pyridine- N-oxide; L 3=pyridine- N-oxide; L 4=3-picoline- N-oxide; L 5=quinoline- N-oxide; L 6=iso-quinoline- N-oxide; L 7=4-methoxyl-pyridine- N-oxide; n=0, 1, 2, 5), were synthesized and characterized by means of elemental analysis, electrical conductivity, thermal analysis and IR spectra. The novel crystal structure of ErL 3L 3 2·(EtOH) has been determined by a single-crystal X-ray diffraction method. It shows that each erbium ion is linked to three 3,5-di- tert-butyl-γ-resorcylic acid ions through two different types of dentation modes in which only the carboxylate oxygen atoms participate. The coordination geometries of erbium ion can be described as a distorted octa-coordinated bicapped trigonal prism.