Phosphane coordination to rare earth metal centers: monomeric, solvent-free complexes of type Cp '(2)LnX with phosphanoethyl substituted cyclopentadienyl ligands

The reaction of phosphanoethyl substituted cyclopentadienides [C5H4CH2CH2PR 2]M, R = Me, Cy, t-Bu, Ph, M = Li, K with LnX(3) (Ln = rare earth metal, X= Cl-, CF3SO3-) afforded twofold substituted metal complexes of the type (C5H 4CH2CH2PR2](2)LnX. Using the dianionic ligand Li-2[(C5H4CH2CH2)(2)PMe] phos phano bridged ansa metallocene derivatives [(C5H4CH2CH2)(2)PMe]LnX( (Ln = Y , Lu; X = Cl-, CF3SO3-) were isolated. The complexes are soluble in toluene , monomeric and free of solvent. According to X-ray studies on [C5H4CH2CH2P Me2](2)YCl, a distorted trigonal bipyramid with two axial phosphano groups and two equatorial cyclopentadienyl moieties is the structural motif, the t hird equatorial site being occupied by the halide ligand. (C) 2000 Elsevier Science S.A. All rights reserved.