Amide Oxygen-Assisted Palladium-Catalyzed Hydration of Alkynes.

Herein, an amide oxygen-assisted palladium-catalyzed hydration reaction of alkynes is realized to prepare a series of o-acylacetanilide derivatives with high yield, and single regioselectivity under mild reaction conditions. This transformation is simple, practical, and can be performed on a gram scale. Evaluation of the mechanism shows that the reaction should involve an oxypalladation process, and the 1,3-oxazine compound is proven to be a key intermediate.