Novel Low-Coordinate Lanthanoid(II) and -(III) Aryloxide Complexes the X-ray Structures of Bis(2,6-diphenylphenolato)tris(tetrahydrofuran)ytterbium(II), Bis(1,2-dimethoxyethane)bis(2,6-diphenylphenolato)ytterbium(II), and 1,2-Dimethoxyethanetris(2,6-diphenylphenolato)ytterbium(ill) and -neodymium(III)

Article abstract of DOI:10.1002/cber.19971300707

Reduction of [Yb(Odpp)₃(THF)₂] (HOdpp = 2,6-diphenylphenol; THF = tetrahydrofuran) with ytterbium powder and mercury metal yields [Yb(Odpp)₂(THF)₃] (1) which on crystallization from DME gives [Yb(Odpp)₂(DME)₂] (2) (DME = 1,2-dimethoxyethane). Crystallization of the reactant [Yb(Odpp)₃(THF)₂] from DME yields [Yb(Odpp)₃(DME)] · (DME)_0.5(3) and of [Nd(Odpp)₃(THF)₂] from DME/THF the analogous [Nd(Odpp)₃(DME)] ·(THF) (4). The X-ray crystal structure of 1 reveals distorted trigonal bipyramidal fivecoordinate ytterbium with axial Odpp ligands [O-Yb-O 164.6(3)°], and unsymmetrically distributed equatorial THF ligands [O-Yb-O 137.5(3), 138.8(3), 83.7(4)°] owing to two close H(Ph)-Yb approaches (3.1-3.2 A). In 2, there is trigonal prismatic six-coordination with an Odpp ligand on each triangular face and DME ligands bridging the triangular faces. Both 3 and 4 have distorted square planar five-coordination for the lanthanoid metals with an apical Odpp ligand and cisoid Odpp ligands and a chelating DME in the square plane. VCH Verlagsgesellschaft mbH,.