Synthesis and structure of [Sm(eta(5)-CpPPh2)(kappa(3)-Tp(Me2))(I)(THF)]; a samarium complex with four different ligands

The mixed-ligand complex, [Sm(CpPPh2)(Tp(Me2))(I)(THF)] (1), was prepared i n moderate yield (55%) by the redox reaction between SmI2 and Tl[CpPPh2] in THF at ambient temperature followed by direct treatment with KTp(Me2). Com plex 1 was fully characterized by elemental analysis, FT-IR, MS and multinu clear NMR (H-1, B-11 and P-31) spectroscopies. The solid-state structure wa s established by single crystal X-ray crystallography. The coordination geo metry of the samarium is best described as distorted tetrahedral with the a pexes occupied by four different ligands; Tp(Me2), CpPPh2, I- and THF. Vari able temperature H-1-NMR spectroscopic investigation confirmed that the chi ral. asymmetric structure is maintained in solution at low temperatures. (C ) 2001 Elsevier Science B.V. All rights reserved.