Asymmetric Synthesis of β-Amino Nitrites through a Sc~(III)-Catalyzed Three-Component Mannich Reaction of Silyl Ketene Imines

摘要

Chiral β-amino nitriles are versatile synthetic intermediates that are readily transformed into optically active compounds such as β-amino acids, and 1,3-diamines. The asymmetric addition of alkyl nitriles to imines provides a straightforward route to such compounds. Although many methods for the asymmetric Mannich reaction have been described, the use of less nucleophilic alkyl nitriles as the nitrile species is a continuing challenge; one reason for this issue is the poor acidity of the a protons of alkyl nitriles.