Thermal and photochemical behaviour of organotetraruthenium clusters: solution structures and dynamics of phosphine-substituted derivatives

Abstract

The thermal and photochemical behaviour of the organotetraruthenium clusters [Ru₄(CO)₁₂(PhC₂R)](R = Me or H) and [Ru₄(CO)₁₁(PhC₂Me)₂] is described. Interestingly the reactions of these complexes with phosphorus donor ligands are highly regioselective, as determined by variable-temperature n.m.r. studies. The dynamic behaviour of [Ru₄(CO)₁₀{P(OMe)₃}(PhC₂Me)₂] shows for the first time the occurrence of a ‘merry-go-round’ CO exchange process around the quasi-planar Ru₄ framework.