Organocatalytic asymmetric tandem condensation-intramolecular rearrangement-protonation: an approach to optically active α-amino thioester derivatives.

An unprecedented and conceptually novel chiral Brønsted base/Brønsted acid catalytic method for the enantioselective synthesis of α-amino thioesters through a tandem condensation-intramolecular rearrangement-protonation has been developed which provides a number of important synthetic building blocks in good yield and with moderate to good enantioselectivities.