Insertion of carbodiimide into the LnN σ-bond of organolanthanide complexes. Synthesis and characterization of organolanthanide guanidinates (C5H5)2Ln[iPrNC(NiPr2)∴NiPr] (Ln=Yb, Dy, Gd)

The synthesis and structures of three new lanthanide complexes incorporating tetra-substituted guanidinate ligand [iPrN∴C(NiPr2)∴NiPr] are described. Treatment of Cp2LnNiPr2(THF) (Ln=Yb, Dy, Gd) with N,N′-di-isopropyl-carbodiimide results in mono-insertion of carbodiimide into the LnN σ-bond to yield Cp2Ln[iPrN∴C(NiPr2)∴NiPr] (Ln=Yb(1), Dy(2), Gd(3)), providing an efficient method for the synthesis of organolanthanide guanidinate complexes. It was found that an excess of N,N′-di-isopropyl-carbodiimide did not affect the nature of the final product. Complexes 1–3 were characterized by elemental analysis, IR and mass spectroscopies. Complexes 1 and 2 were determined by the X-ray single crystal diffraction analysis.