STUDIES ON ORGANOLANTHANIDE COMPLEXES .60 . SYNTHESIS AND CHARACTERIZATION OF ORGANOLANTHANIDE COMPLEXES CONTAINING LN-C OR LN-N SIGMA-BONDS

The new Ln-C sigma-bond complexes bis(2-methoxyethylcyclopentadienyl)a lkynyl lanthanum and ytterbium have been synthesized respectively by t he displacing reaction of bis(2-methoxyethylcyclopentadienyl )lanthani de chlorides( Ln = La,Yb)with sodium alkynyl in THF at - 20 degrees C with 77% and 66% yields. The new Ln-N sigma-bond complexes ethoxyethyl cyclopentadienyl)bis(bis-trimethylsilyl amido) ytterbium or yttrium we re directly prepared by the one-pot reaction of sodium 2-methoxyethylc yclopentadienyl, lithium bis-trimethylsilyl amido and ytterbium or ytt rium trichlorides at 0 similar to 5 degrees C with 56% and 72% yields, respectively. These complexes have been characterized by elemental an alyses, IR, MS, and H-1 NMR spectra. They may be neutral and unsolvate d monomers with the intramolecular coordination bonds between lanthani de metal and ligand oxygen atoms.