Synthesis and characterization of half- and full-sandwich lanthanacarboranes of the C2B9-carborane ligand. X-ray crystal structures of [LnCl(2)(THF)(5)][nido-C2B9H12] (Ln = Y, Yb)

Treatment of LnCl(3)(THF)(x) with one equivalent of Na-2[nido-7,8-C2B9H11] in THF gave the half-sandwich lanthanacarborane chloride compound (eta5-C2B 9H11)Ln(THF)(2)(mu -Cl)(2)Na(THF)(2) (Ln = Y (1), Er (2), Yb (3), Lu (4)). Recrystallization of 1 or 3 from a wet THF-toluene solution afforded the io nic compound [LnCl(2)(THF)(5)][nido-C2B9H12] (Ln = Y (5), Yb (6)). Reaction of I or 3 with Na-2[nido-7,8-C2B9H11] in a molar ratio of 1:1 in THF gener ated the full-sandwich lanthanacarborane {(eta (5)-C2B9H11)(2)Ln(THF)(2)) { Na(THF)(2)} (Ln = Y (7), Yb (8)). AU of these new compounds were characteri zed by H-1-, C-13-, and B-11-NMR spectra and elemental analyses. The solid- state structures of 5 and 6 were further confirmed by single-crystal X-ray analyses. (C) 2000 Elsevier Science B.V. All rights reserved.