Intermolecular Dehydrative Coupling Reaction of Aryl Ketones with Cyclic Alkenes Catalyzed by a Well-Defined Cationic Ruthenium−Hydride Complex: A Novel Ketone Olefination Method via Vinyl C−H Bond Activation

The cationic ruthenium−hydride complex [(η6-C6H6)(PCy3)(CO)RuH]+BF4− was found to be a highly effective catalyst for the intermolecular olefination reaction of aryl ketones with cycloalkenes. The preliminary mechanistic analysis revealed that an electrophilic ruthenium−vinyl complex is the key species for mediating both vinyl C−H bond activation and the dehydrative olefination steps of the coupling reaction.