Oxidative-addition of germanium–hydrogen bonds to triosmium centers: Reactions of Os 3 (CO) 10 (μ-dppm) and Os 3 (CO) 8 (μ 3 -Ph 2 PCH 2 P(Ph)C 6 H 4 )(μ-H) with Ph 3 GeH

Reactions of the triosmium clusters Os3(CO)10(μ-dppm) [dppm = bis(diphenylphosphino)methane] and Os3(CO)8(μ3-Ph2PCH2P(Ph)C6H4)(μ-H) with Ph3GeH are described. With Os3(CO)10(μ-dppm) at 110 °C the oxidative-addition product Os3(CO)9(GePh3)(μ-dppm)(μ-H) (1) initially results, but further decarbonylates upon prolonged heating to give 46-electron Os3(CO)7(GePh3)(μ3-Ph2PCH2P(Ph)C6H4)(μ-H)2 (2) resulting from C–H bond activation of the diphosphine. The pre-activated Os3(CO)8(μ3-Ph2PCH2P(Ph)C6H4)(μ-H) reacts with Ph3GeH under milder conditions (40 °C) to afford Os3(CO)8(GePh3)2(μ-dppm)(μ-H)2 (3) together with 1. Cluster 3 converts into 2 upon heating and the direct reaction between Os3(CO)8(μ3-Ph2PCH2P(Ph)C6H4)(μ-H) and Ph3GeH at 110 °C also produces 2. All these clusters have been structurally characterized by single crystal X-ray diffraction analysis.