Amine-Salt-Controlled, Catalytic Asymmetric Conjugate Addition of Various Amines and Asymmetric Protonation

The combined use of chiral Pd complex 2 and amine salt enabled completely regulated release of free nucleophilic amine. Under these conditions, an efficient catalytic asymmetric conjugate addition of various amines was achieved to afford β-amino acid derivatives in high chemical yields with up to 98% ee. Furthermore, a highly enantioselective protonation in 1,4-addition of amine was also developed.