Routes to ruthenium-cobalt clusters and dicobalt complexes with new alkoxysilyl- or sulfur-functionalized alkynes.: X-ray structures of [NEt4][RuCo3(CO)10{μ4-η2-HC2(CH2)2OC(O)NH(CH2)3Si(OEt)3}] and [Co2(CO)6{μ2-η2-HC2CH2NHC(O)NH(CH2)3Si(OEt)3}]

Two general approaches are presented and compared to covalently link metal clusters to alkynes terminated with a trialkoxysilyl or a thioether group. They consist in the direct reaction of the functional alkyne with the cluster or in the functionalization of an alkyne already coordinated to the cluster. These are applied to the tetrahedral mixed-metal cluster [NEt4] [RuCo3(CO)(12)] (NEt(4)(.)1). Complexes with the new alkynes HCdropC(CH2)(2)-OC(O)NH(CH2)(3)Si(OEt)(3) (L-1), HCdropCCH(2)NHC(O)NH(CH2)(3)Si(OEt)(3) (L-2), and HCdropCCH(2)-NHC(O)NHC6H4SMe (L-3) have been characterized, and the crystal structures of [NEt4]-[RuCo3(CO)(10){mu(4)-eta(2) -HC2(CH2)(2)OC(O)NH(CH2)(3)Si(OEt)(3)}] (NEt(4)(.)2a) and [Co-2(CO)(6){mu(2)-eta(2)- HC2CH2NHC(O)NH(CH2)(3)Si(OEt)(3)}] (9) have been determined by X-ray diffraction.