The nature of alkyne oligomerization on the face of a mixed-metal trinuclear cluster

Article abstract of DOI:10.1021/om00153a036

RuMo₂(CO)₇(μ₃-S)(C₅H ₅)₂ (1) reacts with PhC≡CH by the addition and coupling of 3 equiv to yield RuMo₂(CO)₂(μ₃-S)(C₅H ₅)₂[μ₃-η ⁶-HCC(Ph)CHC(Ph)CHC(Ph)] (2) in 15% yield and RuMo₂(CO)₂(C₅H₅) ₂(μ₃-S)[μ-η ³-(Ph)-CC(H)C(Ph)][μ₃-η³-(H)CC(Ph)CH] (3) in 11% yield. Compound 2 contains a μ₃-HCC(Ph)CHC(Ph)CHC(Ph) ligand that was formed by the addition and head-to-tail coupling of three PhC≡CH molecules. This ligand was split by the cleavage of a carbon-carbon bond to yield two dimetallaallyl ligands that are coordinated to a face and the MoMo edge of the cluster in 3.