Synthesis and properties of homoleptic 2,2′-bipyridyl complexes of rare-earth elements. Crystal and molecular structures of the complexes Ln(N2C10H8)4 (Ln=Sm, Eu, Yb, or Lu) and the ionic complex [Lu(N2C10H8)4][Li(THF)4]

Autor: Tatyana V. Petrovskaya, Igor L. Fedushkin, Frank Girgsdies, Vladimir I. Nevodchikov, Mikhail N. Bochkarev, Herbert Schumann, Roman Weimann
Rok vydání: 2000
Předmět:
Zdroj: Russian Chemical Bulletin. 49:1869-1876
ISSN: 1573-9171
1066-5285
Popis: Homoleptic 2,2′-bipyridyl complexes of lanthanides (Ln), Ln(bpy)4, were prepared by the reactions of iodides LnI2(THF)2 (Ln=Sm, Eu, Tm, or Yb), LnI3(THF)3 (Ln=La, Ce, Pr, Nd, Gd, or Tb), or bis(trimethylsilyl)amides Ln[N(SiMe3)2]3 (Ln=Dy, Ho, Er, or Lu) with bipyridyllithium in tetrahydrofuran (THF) or 1,2-dimethoxyethane in the presence of free 2,2′-bipyridine. The IR and ESR spectral data, the magnetic susceptibilities, and the results of X-ray diffraction analysis indicate that the complexes of all elements of the lanthanide series, except for the europium complex, contain Ln+3 cations and anionic bpy ligands. According to the X-ray diffraction data, the coordination polyhedra about the Sm and Eu atoms are cubes, whereas the environment about the Yb atom is a distorted dodecahedron. In the ionic complex [Lu(bpy)4][Li(THF)4], the geometry of the [Lu(bpy)4]− anion is similar to that of the Lu(bpy)4 complex. The possible modes of charge distributions over the ligands,viz., Ln(bpy2−)(bpy.−)(bpy0)2 and Ln(bpy.−)3(bpy0), are discussed.
Databáze: OpenAIRE
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