Structural optimization of thiourea-based bifunctional organocatalysts for the highly enantioselective dynamic kinetic resolution of azlactones

Org Biomol Chem. 2006 Dec 7;4(23):4319-30. doi: 10.1039/b607574f. Epub 2006 Nov 1.

Abstract

This article describes the synthesis of a library of structurally diverse bifunctional organocatalysts bearing both a quasi-Lewis acidic (thio)urea moiety and a Brønsted basic tertiary amine group. Sequential modification of the modular catalyst structure and subsequent screening of the compounds in the alcoholytic dynamic kinetic resolution (DKR) of azlactones revealed valuable structure-activity relationships. In particular, a "hit-structure" was identified which provides e.g.N-benzoyl-tert-leucine allyl ester in an excellent enantiomeric excess of 95%.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amines / chemistry*
  • Catalysis
  • Combinatorial Chemistry Techniques
  • Crystallography, X-Ray
  • Diamines / chemistry
  • Kinetics
  • Lactones / chemistry*
  • Stereoisomerism
  • Thiourea / analogs & derivatives
  • Thiourea / chemistry*

Substances

  • Amines
  • Diamines
  • Lactones
  • Thiourea