Weinreb Amide Directed Versatile C−H Bond Functionalization under (η 5 ‐Pentamethylcyclopentadienyl)cobalt(III) Catalysis

The (η 5 ‐pentamethylcyclopentadienyl)cobalt(III) (Cp*Co III )‐catalyzed C−H bond functionalization of aromatic, heteroaromatic, and α,β‐unsaturated Weinreb amides was explored. C−H allylation reactions with the use of allyl carbonate and a perfluoroalkene, oxidative alkenylation reactions with the use of ethyl acrylate, iodination reactions with the use of N ‐iodosuccinimide, and amidation reactions with the use of dioxazolones were catalyzed by Cp*Co(CO)I 2 in the presence of a cationic Ag salt and AgOAc to afford various synthetically useful building blocks. Mechanistic studies of the C−H allylation disclosed that the C−H activation step was rate determining and virtually irreversible.