ACTIVATION OF A C-O BOND BY REACTION OF A TRIS(CYCLOPENTADIENYL)LANTHANIDE COMPLEX WITH AN ALKALI-METAL IN DIMETHOXYETHANE (DME) - CRYSTAL-STRUCTURES OF [ND(ETA-C5H3(SIME(3))(2)-1,3)(2)(MU-OME)(2)LI(DME)] AND [(CE(ETA-C(5)H(3)(T)BU(2)-1,3)(2)(MU-OME))(2)]

The reaction of [LnCp''(3)] [Ln = Ce, Cp'' = eta-C(5)H(3)(t)Bu(2)-1,3 or eta-C5H3(SiMe(3))(2)-1,3; or Ln = Nd and Cp'' = eta-C5H3(SiMe(3))(2)-1,3] with metallic lithium or potassium in dimethoxyethane (DME) at ambient temperature gave in high yield [{LnCp''(2)(mu-OMe)}(2)] [Ln = Ce and Cp'' = eta-C5H3(SiMe(3))(2)-1,3 (1) or eta-C(5)H(3)(t)Bu(2)-1,3 (2); or Ln = Nd and Cp'' = eta-C5H3(SiMe(3))(2)-1,3 (3)] or [NdCp''(2)(mu-OMe)(2)Li(DME)] (Cp'' = eta-C5H3(SiMe(3))(2)-1,3) (4). The crystal structures of complexes 2 and 4 are reported. Complex 4 is the first structurally characterized heterobimetallic lanthanocene-alkoxo-lithium.