Catalytic α‑Hydroarylation of Acrylates and Acrylamides via an Interrupted Hydrodehalogenation Reaction

The palladium-catalyzed, α-selective
hydroarylation of acrylates
and acrylamides is reported. Under optimized conditions, this method
is highly tolerant of a wide range of substrates including those with
base sensitive functional groups and/or multiple enolizable carbonyl
groups. A detailed mechanistic study was undertaken, and the high
selectivity of this transformation was shown to be enabled by the
formation of a [PdII(Ar)­(H)] intermediate, which performs
selective hydride insertion into the β-position of α,β-unsaturated
carbonyl compounds.