Mechanism for the Reaction of CO with Oxorhenium Hydrides: Migratory Insertion of CO into Rhenium Hydride and Formyl Bonds leads to Migration from Rhenium to the Oxo Ligand

Computational studies
(M06) have been performed in synergy with
experimental studies to show that the thermodynamics for insertion
of CO into an oxorhenium–hydride bond to form a formyl ligand
is favorable despite conventional wisdom to the contrary. Further,
it is shown that insertion of CO into formyl ligands to form α-dicarbonyl
ligands is also a viable pathway and results in hydroxy carbonyl or
formate complexes, depending on the nature of the ancillary ligand.