Synthesis and structure of [Sm(η5-CpPPh2)(κ3-TpMe2)(I)(THF)]; a samarium complex with four different ligands

The mixed-ligand complex, [Sm(CpPPh2)(TpMe2)(I)(THF)] (1), was prepared in moderate yield (55%) by the redox reaction between SmI2 and Tl[CpPPh2] in THF at ambient temperature followed by direct treatment with KTpMe2. Complex 1 was fully characterized by elemental analysis, FT-IR, MS and multinuclear NMR (1H, 11B and 31P) spectroscopies. The solid-state structure was established by single crystal X-ray crystallography. The coordination geometry of the samarium is best described as distorted tetrahedral with the apexes occupied by four different ligands; TpMe2, CpPPh2, I− and THF. Variable temperature 1H-NMR spectroscopic investigation confirmed that the chiral, asymmetric structure is maintained in solution at low temperatures.