Crown ether complexation of cationic lanthanide(III) chloride species: Crystal and molecular structures of [DyCl2(H2O)(2)(12-crown-4)]-[SbCl6].5THF (1), and [Er(12-crown-4)(2)(MeCN)][SbCl6](3) (2)

摘要

Halide abstraction from a lanthanide(III) chloride using antimony(v) chloride as abstractor provides cationic metal species which can be stabilized in situ by crown ether complexation, The syntheses and structures of two such antimon(v)ate salts are presented, For [DyCl2(12-crown-4)(H2O)2][SbCl6]. 5THF (1) the structure comprises independent [DyCl2(12-crown-4)(H2O)(2)](+) cations and SbCl6- anions with lattice solvent (tetrahydrofuran) molecules, The cation structure has an approximate two-fold axis and the eight-coordinate metal environment can be considered as distorted square-antiprismatie. The Dy-Ofcrown) bond distances are equivalent 2.515(11) A, the Dy-O bond distances are 2,631(5), 2.646(4) Angstrom and the Dy-O(H2O) bond distances are 2,364(10), 2,373(11) Angstrom, In the case of [Er(12-crown-4)(2)(MeCN)][SbCl6](3) (2) the independent nine-coordinate [Er(12-crown-4)(2)(MeCN](3+) cations show crystallographic Ct symmetry with each metal centre being bonded to all four oxygen atoms of the two rings and to a nitrogen atom of a coordinated acetonitrile molecule. The Er-O(crown) bond lengths lie in the range 2.443(9)-2,503(9) Angstrom, mean 2.463(9) Angstrom and the Er-N bond length is 2.56(2) Angstrom, The planes of the two era-crown rings intersect at an angle of 73.0(1)degrees. [References: 18]