Alkoxysilyl-functionalized mixed-metal carbonyl clusters

The new ligand (Ph(2)P)(2)N(CH2)(3)Si(OEt)(3) (L) is reported and used to functionalize metal-metal bonded, heterometallic complexes. Reaction of [Pd2Cl2(mu-Ph(2)PNRPPh(2))] 1 (R = -(CH2)(3)Si(OEt)(3)) with two equiv of Na[Co(CO)(4)] yielded the tetranuclear cluster [Pd2Co2(CO)(7)- (mu-Ph(2)PNRPPh(2))(2)] 2. Since attempts to add a third ligand L to 2 led to complex mixtures, we explored an alternative strategy to achieve maximum functionalization: reaction of [Pd-2(mu-Ph(2)PNHPPh(2))(2)Cl-2] with Na[Co(CO)(4)] afforded [Pd2Co2(CO)(7)(mu-Ph(3)PNHPPh(2))(2)] 3 which was subsequently transformed in [Pd2Co(CO)(2)(mu-Ph(2)PNHPPh(2))(3)] + [PF6]- 4. Treatment of the latter with excess KH and I(CH2)(3)Si(OMe)(3) afforded the mixed-metal Cluster [Pd2CO(CO)(2)(mu-Ph(2)Ph(2)PNRPPh(2))(3)](+) [PF6]- 5 which contains 3 functional assembling ligands.