Access to Chiral Dihydro-1,4-Benzoxazine-2-Carboxylates through NHC-Catalyzed Dynamic Kinetic Resolution

A chiral carbene-catalyzed dynamic kinetic resolution for the facile synthesis of enantioenriched dihydro-1,4-benzoxazine-2-carboxylates is disclosed. The reaction conditions are mild, and a diversity of substituents are well-tolerated in this transformation. In addition, our methodology also provides an efficient strategy for building chiral chromane-2-carboxylate and 2,3-dihydro-1,4-benzodioxane-2-carboxylate. The optically pure products generated from this protocol can be easily derived as the key intermediates of chiral drugs and bioactive molecules.