Asymmetric direct α-hydroxylation of β-oxo esters catalyzed by chiral quaternary ammonium salts derived from cinchona alkaloids

J Org Chem. 2012 Nov 2;77(21):9601-8. doi: 10.1021/jo3016242. Epub 2012 Oct 18.

Abstract

Cinchona alkaloid-derived chiral quaternary ammonium organocatalysts were developed. The catalyst with a bulky 1-adamantoyl group at the C-9 position promoted the enantioselective α-hydroxylation of β-oxo esters and resulted in the corresponding products in 35-95% yields and 58-90% ee. The reaction was successfully scaled to a gram-quantity scale with a similar yield without loss of enantioselectivity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Cinchona Alkaloids / chemistry*
  • Esters
  • Hydroxylation
  • Molecular Structure
  • Quaternary Ammonium Compounds / chemistry*
  • Salts / chemistry*
  • Stereoisomerism

Substances

  • Cinchona Alkaloids
  • Esters
  • Quaternary Ammonium Compounds
  • Salts