Reaction mechanisms of metal–metal bonded carbonyls. Part 12. Reactions of decacarbonylmanganeserhenium, decacarbonylditechnetium, and their bis(triphenylphosphine) derivatives

Abstract

The kinetics of the following reactions in decalinhave been studied : the complexes [MnRe(CO)₁₀] and [Tc₂(CO)₁₀] with triphenylphosphine, [MnRe(CO)₈(PPh₃)₂] and [Tc₂(CO)₈(PPh₃)₂] with carbon monoxide, and decomposition of [Tc₂(CO)₁₀] under oxygen. The results are consistent with initial reversible homolytic fission of the metal–metal bonds so that the activation enthalpies for the rate-limiting steps can be taken as a kinetic measure of the strengths of the metal–metal bonds. Attention is drawn to correlations between the activation enthalpies for the decacarbonyls and spectroscopic parameters related to the bond strengths.