Abstract
The homoleptic tris(substituted cyclopentadienyl)lanthanide(III) complexes [LnCp
R
3] (Ln=La (
1), Ce (
2), Pr (
3), Nd (
4), Sm (
5), Gd (
6), Tb (
7), Dy (
8), Er (
9), Tm (
10) and Yb (
11)], [NdCp
t
3] (
12), [CeCp
tt
3] (
13) and [NdCp
tt
3] (
14) [Cp
R=η
5-C
5H
4{CH(SiMe
3)
2, Cp
t=η
5-C
5H
4(SiMe
2Bu
t), Cp
tt=η
5-C
5H
3(SiMe
2Bu
t)
2-1,3], have been synthesised by the reaction of the anhydrous lanthanide(III) halide with the appropriate sodium or potassium cyclopentadienide in THF. The characterisation of these complexes was established by
1H-,
13C- and
29Si-NMR spectroscopy (for
1–5 and
12–14), elemental analysis and mass spectrometry. The early paramagnetic lanthanide complexes
2–
5, and
12–
14 had very sharp
1H-NMR spectral signals, and the paramagnetic shifts were temperature-dependent. The molecular structures of
4,
10 and
13 have been determined by single crystal X-ray diffraction studies. The attempted syntheses of organoneodymium(II) and organothulium(II) complexes are also described.