A Novel Highly Selective Chiral Auxiliary for the Asymmetric Synthesis of <scp>l</scp>- and <scp>d</scp>-α-Amino Acid Derivatives via a Multicomponent Ugi Reaction
the synthesis of a bicyclic β-amino acid scaffold in both pure enantiomeric forms and its application as chiralauxiliary in an intramolecular version of the Ugi multicomponent reaction (U-5C-4CR) to prepare α-amino acid derivatives of both d- and l-series in a straightforward and very stereoselective manner. The mild conditions required for the Ugi condensation and for the removal of the chiral auxiliary