Catalytic Asymmetric Intramolecular Domino Allylic O-Alkylation/Allylic Dearomatization of Allyl Aryl Ethers.

An intramolecular asymmetric allylic O-alkylation/allylic dearomative spirocyclization cascade has been successfully developed with allyl aryl ethers. In the presence of palladium and a phosphoramidite ligand, a series of spirocyclohexadienones with an exocyclic double bond were obtained in up to 98% yield with 98% ee. The asymmetric allylic alkylation mechanism was elucidated through control experiments. In addition, scale-up of the reaction and further transformations of the spirocyclic products were also performed, demonstrating the potential application of this method.