Highly enantioselective synthesis of 3-amino-2-oxindole derivatives: catalytic asymmetric alpha-amination of 3-substituted 2-oxindoles with a chiral scandium complex

Chemistry. 2010 Jun 11;16(22):6632-7. doi: 10.1002/chem.201000126.

Abstract

A highly enantioselective alpha-amination of 3-substituted oxindoles with azodicarboxylates catalyzed by a chiral Sc(OTf)(3)/N,N'-dioxide complex (Tf: triflate) has been developed and affords the corresponding 3-amino-2-oxindole derivatives in high yields (up to 98%) with excellent enantioselectivities (up to 99% ee). The procedure is capable of tolerating a relatively wide range of substrates, and excellent results (92-96% ee) can also be obtained, even in the presence of 0.5 mol % of catalyst loading under mild conditions. These results showed the potential value of the catalytic approach. Moreover, with high synthetic versatility, the product could be easily transformed into optically active 3-amino-3-methyloxindole bearing a chiral quaternary stereogenic center.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amination
  • Catalysis
  • Crystallography, X-Ray
  • Indoles / chemical synthesis*
  • Indoles / chemistry*
  • Models, Molecular
  • Molecular Structure
  • Organometallic Compounds / chemistry*
  • Oxindoles
  • Scandium / chemistry*
  • Stereoisomerism

Substances

  • 3-amino-2-oxindole
  • Indoles
  • Organometallic Compounds
  • Oxindoles
  • 2-oxindole
  • Scandium