N‐Heterocyclic Carbene‐Catalyzed Enantioselective Intramolecular Annulations to Construct Benzo‐Fused Pyranones with Quaternary Stereocenter.

A highly enantioselective intramolecular NHC‐catalyzed approach for the synthesis of benzo‐fused pyranones bearing quaternary stereocenter is described. The developed methodology is based on annulation reaction between acyl anion intermediates and β,β‐disubstituted Michael acceptors. The reaction offers streamlined and effective access to target products in a highly stereoselective manner. [ABSTRACT FROM AUTHOR]