Synthesis, characterization and structure of the complexes of lanthanide nitrates with 1,8-bis(quinolyloxy)-3,6-dioxaoctane

The lanthanide nitrate complexes with 1,8-bis(quinolyloxy)-3,6-dioxaoctane (L) have been prepared in tetrahydrofuran. These new complexes with the general formula [Ln(NO3)(3)(OH2)(3)](2) . L(3) (Ln = La, Nd, Sm, Er, Y) have been characterized by elemental analysis, IR spectra and conductivity measurements. The structure of the complex [Er(NO3)(3)(OH2)(3)](2) . L(3) . 2H(2)O has been determined by single crystal X-ray diffraction. The erbium(III) ion is nine-coordinate, bonded to three bidentate nitrate groups and three water molecules. The acyclic oligoether molecule is hydrogen bonded to these three coordinated water molecules. The average Er-O(nitrate) and Er-O(water) distances are 2.421(4)Angstrom and 2.307(4)Angstrom, respectively. The average O(water)... O(L) and O(water)... N(L) hydrogen bonded separations are 2.830 Angstrom and 2.795 Angstrom, respectively. The coordination geometry of the erbium(III) ion is a distorted monocapped square antiprism. Copyright (C) 1996 Elsevier Science Ltd