A Ruthenium Dihydrogen Germylene Complex and the Catalytic Synthesis of Digermoxane

A germylene complex with a labile η2-H2 coligand, [RuH2(═GePh2)(η2-H2)(PCy3)2] (2), was isolated in very good yield from the reaction of the bis(dihydrogen) complex [RuH2(η2-H2)2(PCy3)2] (1) with Ph2GeH2. The hydrolytic synthesis of 1,1,3,3-tetraphenyldigermoxane, (HPh2Ge)2O, was catalyzed by 2, 1, and the tricyclopentylphosphine analogue 1Cyp. Coordination of digermoxane by ruthenium led to a complex best formulated as [RuH2({η2-H-GePh2}2O)(PCy3)2] on the basis of X-ray, NMR, IR, and DFT studies.