Substitutional reactivity of dodecacarbonyltrimetal complexes of iron and osmium

Article abstract of DOI:10.1021/om00120a030

The kinetics of the substitution reactions of Fe₃(CO)₁₂ and Os₃(CO)₁₂ have been investigated for L = PPh₃, PBu₃, P(OPh)₃, and P(OMe)₃ in hydrocarbon solution. The substitution of the iron cluster leads to both substitution and fragmentation products with a very small dependence on the entering ligand, typical of a CO dissociative interchange mechanism. Substitution of Fe₃(CO)₁₁PPh₃ leads only to fragmentation at a rate which is faster than substitution on Fe₃(CO)₁₂. Substitution on Os₃(CO)₁₂ occurs in an entering ligand independent reaction to Os₃(CO)₉L₃. The reactivities of these clusters are compared to the ruthenium analogue and to the mononuclear complexes M(CO)₅.