Organolanthanoids. VI. Syntheses of cyclopentadienyllanthanoids by transmetallation reactions between thallous cyclopentadienides and lanthanoid elements

Abstract

Cyclopentadienyllanthanoids (C₅H₅)₃M(thf) (M = Ce, Nd, Sm, Gd or Er; thf = tetrahydrofuran), (C₅H₅)₃M (M = Er or Yb), (MeC₅H₄),M (M = Nd, Sm or Gd), (C₅H₅)₂Yb, (C₅H₅)₂Yb(dme) (dme = 1,2-dimethoxyethane), and (MeC₅H₄)₂Yb(thf), have been synthesized in satisfactory-to-good yield by reaction of the lanthanoid elements with the thallous cyclopentadienides (RC₅H₄)TI (R = H or Me) in tetrahydrofuran or 1,2-dimethoxyethane. The outcome of the reaction of ytterbium with thallous cyclopentadienide [(C₅H₅),Yb; n = 2 or 3] depends on the stoichiometry; it has been shown that (C₅H₅),Yb is reduced by ytterbium metal to (C₅H₅),Yb and that the divalent compound is oxidized to (C₅H₅),Yb by thallous cyclopentadienide. Addition of mercury metal aids initiation of transmetallation, but it is not essential for reaction to occur.