Perfluorophenylboronic acid-catalyzed direct α-stereoselective synthesis of 2-deoxygalactosides from deactivated peracetylated d-galactal

Chem Commun (Camb). 2019 Oct 8;55(81):12204-12207. doi: 10.1039/c9cc06151g.

Abstract

Perfluorophenylboronic acid 1c catalyzes the direct stereoselective addition of alcohol nucleophiles to deactivated peracetylated d-galactal to give 2-deoxygalactosides in 55-88% yield with complete α-selectivity. The unprecedented results reported here also enable the synthesis of disaccharides containing the 2-deoxygalactose moiety directly from the deactivated peracetylated d-galactal. This convenient and metal-free glycosylation method works well with a wide range of alcohol nucleophiles as acceptors and tolerates a range of functional groups without the formation of the Ferrier byproduct and without the need for a large excess of nucleophiles or additives. The method is potentially useful for the synthesis of a variety of α-2-deoxygalactosides.

MeSH terms

  • Acetylation
  • Boronic Acids / chemistry*
  • Catalysis
  • Disaccharides / chemistry
  • Galactose / analogs & derivatives*
  • Galactose / chemistry
  • Galactosides / chemical synthesis*
  • Glycosylation
  • Molecular Structure
  • Solvents / chemistry
  • Stereoisomerism
  • Temperature

Substances

  • Boronic Acids
  • Disaccharides
  • Galactosides
  • Solvents
  • galactal
  • Galactose