One-pot synthesis of pyrrole-2-carboxylates and -carboxamides via an electrocyclization/oxidation sequence

J Org Chem. 2014 Dec 5;79(23):11750-8. doi: 10.1021/jo5021823. Epub 2014 Nov 13.

Abstract

An electrocyclic ring closure is the key step of an efficient one-pot method for the synthesis of pyrrole-2-carboxylates and -carboxamides from chalcones and glycine esters or amides. The 3,4-dihydro-2H-pyrrole intermediates generated in situ are oxidized to the corresponding pyrroles by stoichiometric oxidants or by catalytic copper(II) and air in moderate to high yields. A wide range of functional groups are tolerated, and further combination with an in situ bromination gives access to polyfunctional pyrrole scaffolds.

MeSH terms

  • Catalysis
  • Copper / chemistry
  • Cyclization
  • Electrochemistry
  • Esters
  • Oxidation-Reduction
  • Proline / analogs & derivatives*
  • Proline / chemical synthesis
  • Proline / chemistry
  • Pyrroles / chemical synthesis*
  • Pyrroles / chemistry
  • Stereoisomerism

Substances

  • Esters
  • Pyrroles
  • 2-pyrrolecarboxylic acid
  • Copper
  • Proline