Enantioselective synthesis of hydrobenzofuranones using an asymmetric desymmetrizing intramolecular Stetter reaction of cyclohexadienones

A series of cyclohexadienones were synthesized by dearomatization of phenols followed by Dess-Martin oxidation. Asymmetric intramolecular Stetter reactions of these substrates provide hydrobenzofuranones in good to excellent yields and excellent stereoselectivities. Up to three stereocenters as well as a quaternary stereocenter are formed from polysubstituted substrates. A scale-up experiment demonstrates the utility of this transformation.