Synthesis of six-membered spirocyclic oxindoles with five consecutive stereocenters in an asymmetric organocatalytic one-pot Michael/Michael/aldol addition sequence

J Org Chem. 2013 Apr 5;78(7):2897-907. doi: 10.1021/jo302655u. Epub 2013 Mar 8.

Abstract

An asymmetric organocatalytic one-pot synthesis of six-membered spirocyclic oxindoles has been successfully developed through a relay Michael/Michael/aldol addition reaction catalyzed by the combination of readily available diphenylprolinol silyl ether and bifunctional quinine thiourea. The one-pot protocol affords the highly substituted spirocyclic oxindoles in high yields and perfect enantioselectivities. More importantly, through judicious choice of the organocatalysts employed, this reaction could be readily adapted to predominantly afford an alternative major diastereomer of the product.

MeSH terms

  • Catalysis
  • Indoles / chemical synthesis*
  • Indoles / chemistry
  • Molecular Structure
  • Organic Chemicals / chemistry*
  • Spiro Compounds / chemical synthesis*
  • Spiro Compounds / chemistry
  • Stereoisomerism

Substances

  • Indoles
  • Organic Chemicals
  • Spiro Compounds