Insertion of ketenimines into the ln-c σ-bond of organolanthanides: A new strategy for synthesis of lanthanide 1-azaallyl complexes

摘要

Treatment of [Cp_2Ln(μ-Me)]_2 and Cp_2LnPh with PhRC - C - N~tBu gives the insertion products Cp _2Ln[~tBuNC(R-)CRPh] (R = Ph, R- = Me, Ln = Y (1-Y), Er (1-Er), Yb (1-Yb); R = Ph, R- = Ph, Ln = Y (2-Y), Er (2-Er), Yb (2-Yb); R = H, R-= Me, Ln = Y (3-Y), Er (3-Er), Yb (3-Yb); R = H, R- = Ph, Ln = Y (4-Y), Er (4-Er), Yb (4-Yb)), which represents the first example of ketenimine insertion into a lanthanide-carbon bond and provides an efficient method for the synthesis of organometallic complexes with the 1-azaallyl ligands. It is found that an excess of ketenimine does not affect the nature of the final complexes, with only a monoinsertion product being observed. All these complexes are characterized by elemental analysis and spectroscopic properties. The structures of these complexes have also been determined through X-ray single-crystal diffraction analysis, revealing a novel bonding mode of aryl-substituted azaallyls to a metal.