Cyclopentadienyl complexes of yttrium and the lanthanides with bis(phosphinimino)methanides

Metallocenes of yttrium and the lanthanides with bis(phosphinimino)methanides in the coordination sphere are reported. Reaction of [{CH(PPh2NSiMe3)2-κ2N,N′,κC}LnCl2]2 (Ln=Y, Sm, Er) with Na(C5H5) in a 1:4 molar ratio in THF afforded the corresponding metallocenes [(η5-C5H5)2Ln{CH(PPh2NSiMe3)2-κ2N,N′,κC}]. The structures of these new compounds were investigated in solution and in the solid state. Single crystal X-ray structures show that both imine groups and the methine carbon are bound to the lanthanide atom.