Enantioselective synthesis of benzofurans and benzoxazines via an olefin cross-metathesis–intramolecular oxo-Michael reaction

Chiral phosphoric acid and Hoveyda–Grubbs II were found to catalyze an olefin cross-metathesis–intramolecular oxo-Michael cascade reaction of the ortho-allylphenols and enones to provide a variety of benzofuran and benzoxazine derivatives in moderate to good yields and enantioselectivity.