New Organocatalytic Asymmetric Synthesis of Highly Substituted Chiral 2-Oxospiro-[indole-3,4'- (1',4'-dihydropyridine)] Derivatives

Molecules. 2015 Aug 31;20(9):15807-26. doi: 10.3390/molecules200915807.

Abstract

Herein, we report our preliminary results concerning the first promising asymmetric synthesis of highly functionalized 2-oxospiro-[indole-3,4'-(1',4'-dihydropyridine)] via the reaction of an enamine with isatylidene malononitrile derivatives in the presence of a chiral base organocatalyst. The moderate, but promising, enantioselectivity observed (30%-58% ee (enantiomeric excess)) opens the door to a new area of research for the asymmetric construction of these appealing spirooxindole skeletons, whose enantioselective syntheses are still very limited.

Keywords: 1,4-dihydropyridine; 2-oxospiro-[indole-3,4′- (1′,4′-dihydropyridine)]; chiral base; enamine; enantioselective; isatin; isatylidene malononitrile; organocatalysis; spirooxindole.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Dihydropyridines / chemistry*
  • Indoles / chemistry*
  • Molecular Structure
  • Spiro Compounds / chemistry
  • Stereoisomerism

Substances

  • Dihydropyridines
  • Indoles
  • Spiro Compounds
  • 1,4-dihydropyridine
  • indole