Rational combination of two privileged chiral backbones: highly efficient organocatalysts for asymmetric direct aldol reactions between aromatic aldehydes and acylic ketones

J Org Chem. 2008 Aug 1;73(15):6006-9. doi: 10.1021/jo800910s. Epub 2008 Jun 24.

Abstract

A new class of organocatalysts has been designed by rational combination of proline with cinchona alkaloids. The chiral amine 3a, prepared from l-proline and cinchonidine, has been found to be an efficient catalyst for the direct aldol reactions of acetone or 2-butanone with a wide range of aldehydes (up to 98% ee). The cinchonidine backbone is essential to the reaction efficiency and enantioselectivity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aldehydes / chemistry*
  • Amines / chemistry
  • Catalysis
  • Ketones / chemistry*
  • Molecular Structure
  • Nitrobenzenes / chemistry
  • Stereoisomerism

Substances

  • Aldehydes
  • Amines
  • Ketones
  • Nitrobenzenes
  • 3-hydroxybutanal
  • nitrobenzene