Divergent Total Syntheses of Yaequinolone-Related Natural Products by Late-Stage C–H Olefination

[Image: see text] Divergent total syntheses of 10 yaequinolone-related natural products have been achieved for the first time by late-stage C–H olefination of 3,4-dioxygenated 4-aryl-5-hydroxyquinolin-2(1H)-ones, core structures of this family of natural products. A robust synthetic methodology to construct the core structures has been established, and the C–H olefination reaction has been carried out with synthetically useful yields and high levels of site-selectivity under mild reaction conditions in the presence of a Pd/S,O-ligand catalyst.