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(sp(3))-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.