Asymmetric synthesis of functionalized aza-cyclic amino acids with quaternary stereocenters by a phase-transfer-catalyzed alkylation strategy

Org Lett. 2005 Jan 20;7(2):191-3. doi: 10.1021/ol047921p.

Abstract

[Reaction: see text] Practical asymmetric synthesis of functionalized aza-cyclic alpha-amino acid derivatives possessing quaternary stereocenters has been achieved by the phase-transfer-catalyzed alkylation of 2 or 3 using chiral quaternary ammonium bromide 1 as catalyst. Subsequent reduction and alkylation of the 3-keto carbonyl moiety of 4 proceeded with complete diastereochemical control to afford the corresponding beta-hydroxy aza-cyclic alpha-amino acid derivatives having stereochemically defined consecutive quaternary carbon centers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkylation
  • Amino Acids, Cyclic / chemical synthesis*
  • Amino Acids, Cyclic / chemistry
  • Aza Compounds / chemical synthesis*
  • Aza Compounds / chemistry
  • Catalysis
  • Phase Transition
  • Stereoisomerism

Substances

  • Amino Acids, Cyclic
  • Aza Compounds