Chemistry of the metal carbonyls. Part LXI. Organogermanium (carbonyl)-ruthenium and -osmium complexes

Abstract

Excess of trimethylgermane reacts with dodecacarbonyltriruthenium at 80–100° in hexane forming the polynuclear complexes (Me₃Ge)₂Ru(CO)₄ and [Me₃GeRu(CO)₃(µ-GeMe₂)]₂. However, irradiation of the reactants using a slight excess of the hydride gives the complex [Me₃GeRu(CO)₄]₂ as the major product. Dodecacarbonyltriosmium is less reactive, but at about 150° affords (Me₃Ge)₂Os(CO)₄ and [Me₃GeOs(CO)₃(µ-GeMe₂)]₂, with a low yield of Me₃GeOs(CO)₄H. On irradiation the latter is formed in better yield, but under all conditions no complex [Me₃GeOs(CO)₄]₂ is produced. Thermal decomposition of the complexes (Me₃Ge)₂M′(CO)₄[M′= Ru or Os] at about 160° yields metal-atom clusters [Me₂GeM′(CO)₃]₃ of a new structural type, as well as species (Me₂Ge)₃M′_2^–(CO)₆, both involving bridging Me₂Ge groups. The complex [Me₃GeRu(CO)₄]₂ generates an anion [Me₃GeRu-(CO)₄]^–, on treatment with sodium amalgam, which has been employed in the synthesis of compounds Me₃GeRu-(CO)₄X (X = Me₃Sn, AuPPh₃, and Re(CO)₅]. The reactions of hydrides Me₃MH (M = Ge or Sn) with several of the complexes are described. Trichlorogermane reacts with Ru₃(CO)₁₂ under u.v. irradiation to give cis-(Cl₃Ge)₂Ru-(CO)₄.