Highly enantioselective direct conjugate addition of ketones to nitroalkenes promoted by a chiral primary amine-thiourea catalyst

J Am Chem Soc. 2006 Jun 7;128(22):7170-1. doi: 10.1021/ja0620890.

Abstract

Primary amine-thiourea derivative 1 is an active and highly enantioselective catalyst for the conjugate addition of ketones to nitroalkenes. Broad substrate scope is described, with nitroalkenes bearing either aromatic or aliphatic substituents and a wide variety of ketones shown to be useful reacting partners. Ethyl ketones react preferentially, generating anti products with methyl-bearing stereocenters with good-to-excellent diastereoselectivity. An enamine mechanism is indicated, with cooperative activation of the electrophile by the thiourea and of the ketone by the primary amine.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Alkenes / chemical synthesis*
  • Alkenes / chemistry
  • Amines / chemistry
  • Catalysis
  • Ketones / chemistry*
  • Molecular Structure
  • Nitro Compounds / chemical synthesis*
  • Nitro Compounds / chemistry
  • Stereoisomerism
  • Thiourea / analogs & derivatives*

Substances

  • Alkenes
  • Amines
  • Ketones
  • Nitro Compounds
  • Thiourea