A general and efficient method for the synthesis of highly enantiopure 4-amino-1,2,3,4-tetradydropyridine derivatives based on chiral phosphoric acid catalyzed intramolecular nucleophilic addition of tertiary enamides to imines has been developed. We have also demonstrated a substrate engineering strategy to significantly improve the enantioselectivity of asymmetric catalysis
Key words
tertiary enamides - 1,2,3,4-tetrahydropyridines - asymmetric catalysis - chiral phosphoric acid - substrate engineering