Spirocyclization by Palladium-Catalyzed Domino Heck–Direct C–H Arylation Reactions: Synthesis of Spirodihydroquinolin-2-ones

Treatment of a DMA solution of anilide 1 with a catalytic amount of palladium acetate (0.025 equiv) and XPhos (0.05 equiv) in the presence of potassium carbonate (2.0 equiv) at 100 °C afforded dihydroquinolin-2-ones spiro-fused to dihydrofuranyl, indolinyl, and indanyl 2 in good to excellent yields. The reaction went through a domino sequence involving a 5-exo-trig Heck cyclization followed by an intramolecular direct C-H functionalization.