| Popis: |
Reactivity of Derivatives of Phosphorus Ylides on Ru3 Clusters: Interconversions due to Alkyne Insertion The Ru3 clusters with triply bridging organic ligands derived from phosphorus ylides undergo interconversions by insertion of alkynes. The phosphoniomethylidyne-bridged cluster H2Ru3(CO)9(μ31-C — PPh3) (1) inserts alkynes either into one Ru — H bond (HCCSiMe3, EtCCEt) forming μ21-vinyl-Ru3 complexes or into the Ru3-μ31-C unit (HCCSiMe3, PhCCPh) converting it into a μ31-allyl ligand, e.g. in Ru3(CO)8(PPh3)(μ31-Ph3P — CCHCSiMe3) (6). HCCPh induces fragmentation of 1. The phosphonio enolate-bridged clusters HRu3(CO)9-(μ31-Ph3P — CH — CO) (2a) and HRu3(CO)8(PPh3)(μ31-Ph3P — CH — CO) (2b) insert alkynes (HCCPh, PhCCPh, HCCSiMe3, EtCCEt) into the Ru — H bond to form μ21-vinyl-bridged derivatives, e.g. Ru3(CO)8(μ31-Ph3P — CH — CO)(μ21-RCCHR′) (9). In addition, the alkyne reactions of 2a induce cluster opening with concomitant CO and alkyne incorporation into the organic ligand and formation of an oxaruthenol-derived trinuclear complex 11, as proved by an X-ray structure determination of the PhCCPh product 11b. For the cluster H2Ru3(CO)7(PPh3)(μ31-C6H4Ph2P — C(O)Me) (3) containing an ortho1-metalated phosphonio ketone ligand, only alkyne insertion into one or two Ru — H units is observed. |
Plný text