Amino-indanol-catalyzed asymmetric Michael additions of oxindoles to protected 2-amino-1-nitroethenes for the synthesis of 3,3'-disubstituted oxindoles bearing α,β-diamino functionality

J Org Chem. 2011 May 20;76(10):4008-17. doi: 10.1021/jo2004378. Epub 2011 Apr 18.

Abstract

An organocatalytic asymmetric Michael addition reaction of 3-substituted oxindoles to protected 2-amino-1-nitroethenes has been developed. The reaction is catalyzed by a simple and readily available amino-indanol derivative and affords the desired products in very high yields (up to 99%) with excellent diastereoselectivities (up to >99:1) and very good enantioselectivities (up to 90%). Significantly, this study provides a general catalytic method for the construction of 3,3'-disubstituted oxindoles bearing α,β-diamino functionality as well as vicinal chiral quaternary/tertiary stereocenters. The potential utility of the protocol also had been demonstrated by gram-scale reaction and the versatile conversion of product. Furthermore, On the basis of the comprehensive experimental results and the absolute configuration of one of the Michael adducts, a work model was also proposed to explain the origin of asymmetric induction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amines / chemistry*
  • Catalysis
  • Indans / chemistry*
  • Indoles / chemical synthesis*
  • Indoles / chemistry*
  • Nitro Compounds / chemistry*
  • Oxindoles

Substances

  • Amines
  • Indans
  • Indoles
  • Nitro Compounds
  • Oxindoles
  • aminoindanol
  • 2-oxindole