Palladium-catalyzed Sonogashira coupling of amides: access to ynones via C–N bond cleavage

The first palladium-catalyzed Sonogashira coupling of amides has been developed, which proceeds via a selective cleavage of the N-acylsaccharin C–N bond. The protocol is mild, highly functional group tolerant and can be efficiently employed in the synthesis of a broad array of ynones in 48–98% yields under low catalyst loading and Cu-free conditions.