Hydroxyproline-derived pseudoenantiomeric [2.2.1] bicyclic phosphines: asymmetric synthesis of (+)- and (-)-pyrrolines

J Am Chem Soc. 2014 Aug 27;136(34):11890-3. doi: 10.1021/ja505592h. Epub 2014 Aug 14.

Abstract

We have prepared two new diastereoisomeric 2-aza-5-phosphabicyclo[2.2.1]heptanes from naturally occurring trans-4-hydroxy-L-proline in six chemical operations. These syntheses are concise and highly efficient, with straightforward purification. When we used these chiral phosphines as catalysts for reactions of γ-substituted allenoates with imines, we obtained enantiomerically enriched pyrrolines in good yields with excellent enantioselectivities. These two diastereoisomeric phosphines functioned as pseudoenantiomers, providing their chiral pyrrolines with opposite absolute configurations.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Bridged Bicyclo Compounds / chemical synthesis*
  • Bridged Bicyclo Compounds / chemistry
  • Hydroxyproline / chemistry*
  • Molecular Structure
  • Phosphines / chemical synthesis*
  • Phosphines / chemistry
  • Pyrroles / chemical synthesis*
  • Pyrroles / chemistry
  • Stereoisomerism

Substances

  • Bridged Bicyclo Compounds
  • Phosphines
  • Pyrroles
  • pyrroline
  • Hydroxyproline