Highly enantioselective decarboxylative protonation of alpha-aminomalonates mediated by thiourea cinchona alkaloid derivatives: access to both enantiomers of cyclic and acyclic alpha-aminoacids

Org Lett. 2007 Jul 5;9(14):2621-4. doi: 10.1021/ol070712v. Epub 2007 Jun 19.

Abstract

Thiourea derived cinchona alkaloids promote the asymmetric decarboxylative protonation of cyclic, acyclic, or bicyclic alpha-aminomalonate hemiesters under mild and metal-free conditions to afford enantioenriched aminoesters in high yields and enantioselectivities up to 93%. Both enantiomers of the aminoesters have been synthesized with the same selectivity when using organic base 3 and its pseudoenantiomer 6 derived from quinine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acids, Acyclic / chemistry*
  • Alkaloids / chemistry*
  • Amino Acids / chemistry*
  • Amino Acids, Cyclic / chemistry*
  • Cinchona / chemistry*
  • Decarboxylation
  • Malonates / chemistry*
  • Protons
  • Quinine / chemistry
  • Solvents
  • Stereoisomerism
  • Thiourea / chemistry*

Substances

  • Acids, Acyclic
  • Alkaloids
  • Amino Acids
  • Amino Acids, Cyclic
  • Malonates
  • Protons
  • Solvents
  • Quinine
  • Thiourea