Palladium-Catalyzed (4 + 1) Cycloaddition of Amido-Tethered Allylic Carbonates with Sulfur Ylides: Synthesis of γ-Lactam Derivatives

In this paper, we reported a palladium-catalyzed formal (4 + 1) cycloaddition reaction between amido-tethered allylic carbonates and sulfur ylides. The reaction worked well to provide γ-lactam compounds in satisfactory yields and displayed good compatibility to a wide range of functional groups. The synthetic value of the reaction was demonstrated through scale-up reaction and further transformation. A plausible reaction mechanism was also proposed.