Asymmetric Phosphine‐Catalyzed [4+1] Annulations of o‐Quinone Methides with MBH Carbonates.

Chiral dihydrobenzofuran units are frequently present in molecules with significant biological and pharmaceutical activities. Herein, we present the first enantioselective formal [4+1] annulation of Morita‐Baylis‐Hillman carbonates with o‐quinone methides (o‐QMs) catalyzed by a newly designed chiral phosphine catalyst. Under the mild and eco‐friendly conditions, a wide range of polysubstituted dihydrobenzofurans were obtained in good yields with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]