Palladium-Catalyzed Wacker-Heck Reactions

Significance

A sequential Wacker-Heck reaction of β-hydroxy ynones with ethyl acrylate to give tri-and tetra-substituted dihydropyranones in moderate yields and excellent diastereoselectivities is reported. Under the same conditions, the reaction of racemic α-hydroxy ynones with ethyl acrylate affords tetrasubstituted furanones in moderate yields. The scope of the reaction was inadequately studied. In one starting material, R³ = Ph, a side-product, 2,2-dimethyl-5-phenyl-furan-3-one, was observed.