Ytterbium(+2) indenyl complexes: synthesis and crystal structures of (C9H7)(2)Yb center dot DME, rac-(CH2)(2)(1-C9H6)(2)Yb(THF)(2), and rac-(CH2)(2)[1-(4,7-(CH3)(2)C9H4)]Yb(THF)(2)

Metallation of 2.2-bis(1'-indene)propane by sodium hydride followed by the reaction of the sodium derivative with YbCl3 yields (C9H7)(2)Yb.DME (1), an ytterbium(+2) complex with unlinked indenyl ligands. The reaction between (CH2)(2)(1-Ind')(2)Li-2 and YbCl3 in diethyl ether with subsequent reductio n of the product by sodium metal in THF gives rac-(CH2)(2)(1-Ind')(2) Yb(TH F)(2), where Ind' = C9H6 (2) and 4,7-(CH3)(2)C9H4 (3). The structures of th e complexes were determined by X-ray structural analysis. (C) 1999 Elsevier Science S.A. All rights reserved.