Palladium-Catalyzed β‑Arylation of Silyl Ketene Acetals and Application to the Synthesis of Benzo-Fused δ‑Lactones

Silyl ketene acetals are shown to be competent nucleophiles in Pd-catalyzed migrative C(sp3)–H arylations. Compared to the parent ester lithium enolates, they possess decreased reactivity but enhanced chemoselectivity. This behavior was exploited through the synthesis of valuable benzo-fused δ-lactones such as 1-isochromanones and dihydrocoumarins.