Formation and Molecular Structure of Permethylyttrocene Methyl Tetrahydrofuranate

The reaction of Cp*2YCl · THF with MeLi in THF at -80 °C gives the monomeric Cp*2YMe · THF (1), which has been characterized by spectroscopy, elemental analyses and a single crystal X-ray diffraction study. Complex 1 crystallizes in the orthorhombic space group Pnam with lattice parameters a 17.881(4), b 8.621(2), c 15.095(3) Å, Z = 4, and Dcalc 1.274 g cm-3. Least-squares refinement using 1056 independent observed reflections and 117 parameters gave a final R value of 0.071. The Y-C(σ) bond distance is 2.44(2) Å. IR and NMR spectra indicate an agostic interaction between the metal center and one of the C-H bonds of the methyl ligand, but this could not be confirmed by the X-ray structure determination owing to disorder.