Palladium-Catalyzed Carbonylation/Acyl Migratory Insertion SequenceThe project is supported by NSFC (Grant No. 20832002, 20772003, 20821062), 973 Program (No. 2009CB825300)

Migratory insertion is one of the fundamental processes in organopalladium chemistry. In particular, migratory insertion of a CO ligand and the formation of reactive acylpalladium intermediate is a powerful method for introducing a carbonyl functionality into organic molecules. The catalytic cycle involving such a key step has been developed into one of the most important tools to synthesize various carbonyl compounds. However, for a long time, the scope of migratory insertion processes of organopalladium has been limited to those involving carbon monoxide. In view of the similarity between a carbene and carbon monoxide, one may conceive palladium–carbene as another species which may undergo migratory insertion (Scheme 1). Indeed, the migra-