Synthesis and Characterization of Paramagnetic Lanthanide Benzyl Complexes

The organometallic chemistry of paramagnetic lanthanides
(Ln, from Ce to Yb) is far less developed compared to that of their
diamagnetic counterparts (Sc, Y, La, and Lu). Lack of available starting
materials and characterization methods are the major obstacles. Herein
we report the synthesis and characterization of trisbenzyl complexes
of neodymium, gadolinium, holmium, and erbium. In addition, we introduce
a direct procedure for the synthesis of lanthanide benzyl and iodide
complexes supported by a ferrocene diamide ligand starting from the
corresponding oxides. All newly synthesized compounds were characterized
by X-ray crystallography, 1H NMR spectroscopy (except for
gadolinium compounds, which were NMR silent), and elemental analysis.