Stereoselective synthesis of 1,2-diamine containing indolines by a conjugate addition nitro-Mannich reaction

Org Biomol Chem. 2015 Jan 7;13(1):170-7. doi: 10.1039/c4ob01793e.

Abstract

A conjugate addition nitro-Mannich reaction followed by nitro reduction and intramolecular N-arylation gives diastereomerically pure substituted 1,2-diamine containing indolines. Placing the N-arylation cyclisation handle on the imine precursor derived from an ortho-bromine substituted aromatic aldehyde gave the corresponding β-nitroamines in 55-72% yields as single diastereoisomers. Nitro reduction was effected with modified quantities of Zn/HCl and a subsequent Pd(0) catalysed Buchwald Hartwig cyclisation gave indoline products in 40-70% yields as single diastereoisomers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chemistry Techniques, Synthetic
  • Cyclization
  • Diamines / chemical synthesis*
  • Diamines / chemistry*
  • Indoles / chemistry*
  • Nitro Compounds / chemistry*
  • Palladium / chemistry
  • Stereoisomerism
  • Substrate Specificity

Substances

  • Diamines
  • Indoles
  • Nitro Compounds
  • Palladium
  • indoline