SYNTHESIS AND CRYSTAL-STRUCTURE OF THE ORGANOGERMANIUM COMPLEX OF YTTERBIUM [(PH(2)GE)(4)YB(THF)(4)]CENTER-DOT-4THF WITH A 5-MEMBERED GE4YB CYCLE

The organogermanium complex of ytterbium [(Ph(2)Ge)(4)Yb(THF)(4)]. 4TKF (1) was synthesized by the reaction of metallic ytterbium with Ph(2)GeCl(2) in THF at room temperature. X-ray study has shown that the molecule of (Ph(2)Ge)(4)Yb(THF)(4) is an octahedral Yb complex with the C-2 symmetry. The four coordination positions at the Yb atom are occupied by the oxygen atoms of THF molecules and the two cis-positions are occupied by two terminal germanium atoms of the Ph(2)Ge-GePh(2)-GePh(2)-GePh(2) fragment. Thus, the (Ph(2)Ge)(4)Yb(THF)(4) molecule involves the five-membered Ge4Yb metallocycle with a twist conformation. The Yb-Ge and Yb-O distances are 3.104(2) and 2.475(8), 2.402(10) Angstrom.