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

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.