Metal-Free Deoxygenation of Chiral Nitroalkanes: An Easy Entry to α-Substituted Enantiomerically Enriched Nitriles

Chemistry. 2021 Jul 16;27(40):10247-10250. doi: 10.1002/chem.202100889. Epub 2021 Jun 15.

Abstract

A metal-free, mild and chemodivergent transformation involving nitroalkanes has been developed. Under optimized reaction conditions, in the presence of trichlorosilane and a tertiary amine, aliphatic nitroalkanes were selectively converted into amines or nitriles. Furthermore, when chiral β-substituted nitro compounds were reacted, the stereochemical integrity of the stereocenter was maintained and α-functionalized nitriles were obtained with no loss of enantiomeric excess. The methodology was successfully applied to the synthesis of chiral β-cyano esters, α-aryl alkylnitriles, and TBS-protected cyanohydrins, including direct precursors of four active pharmaceutical ingredients (ibuprofen, tembamide, aegeline and denopamine).

Keywords: chiral nitriles; metal-free reactions; nitroalkanes; stereoselectivity; trichlorosilane.

MeSH terms

  • Amines
  • Catalysis
  • Nitriles*
  • Nitro Compounds*
  • Stereoisomerism

Substances

  • Amines
  • Nitriles
  • Nitro Compounds