Asymmetric synthesis of new β-heterocyclic (S)-α-aminopropionic acids

Abstract: The asymmetric synthesis of novel non-proteinogenic β-heterocyclic α-amino acids via the diastereoselective conjugate addition of heterocyclic nucleophiles to the dehydroalanine moiety of chiral Ni(II) complexes has been studied. The complexes were formed from the Schiff base of dehydroalanine using (S)-2-N-(N-benzylprolyl)aminobenzophenone as a chiral auxiliary. After decomposition of the complexes, the α-amino acids were isolated with 30–99% ee. [Copyright &y& Elsevier]