Construction of chiral 1,4-DHPs by chiral phosphoric acid catalyzed desymmetric reductive amination.

Herein, we report an asymmetric reductive amination reaction catalyzed by a chiral phosphoric acid, which enables the enantioselective desymmetrization of 1,4-dihydropyridine-3,5-dialdehydes. This reaction features mild conditions, high enantioselectivity, and readily available starting materials. Gram-scale experiments demonstrated that the reaction maintained excellent enantioselectivity, and the product could be readily converted into other chiral 1,4-dihydropyridine derivatives. These results underscore the potential of this method for practical applications.