An unexpected palladium-catalyzed cyclization of bis-hydroxy allylic alcohols to dioxabicyclo[2.2.2]octanes

The palladium(II)-catalyzed cyclization of bis-hydroxy allylic alcohols afforded quantitatively a mixture of (3-alkyl-5-vinyltetrahydrofuran-3-yl)methanol and 4-alkyl-1-methyl-2,6-dioxabicyclo[2.2.2]octane.