1,2-Bis(ferrocenyl)digermene: A d−π Electron System Containing a GeGe Unit

The synthesis and structural analysis of the 1,2-bis­(ferrocenyl)­digermene
(E)-Tip­(Fc)­GeGe­(Fc)­Tip (Tip = 2,4,6-triisopropylphenyl,
Fc = ferrocenyl), a stable crystalline compound, is reported. In this
digermene, two ferrocenyl d electron systems are bridged by a GeGe
π spacer. As is evident from X-ray crystallographic, spectroscopic,
and electrochemical analysis, this 1,2-bis­(ferrocenyl)­digermene shows
effective d−π interaction and the GeGe π
bond is stable in the solid state. The GeGe double bond is
cleaved at elevated temperatures in the presence of butadiene, with
concomitant loss of the π conjugation in the molecule.