Asymmetric synthesis of protected α-amino boronic acid derivatives with an air- and moisture-stable Cu(II) catalyst

J Org Chem. 2014 Apr 18;79(8):3671-7. doi: 10.1021/jo500300t. Epub 2014 Mar 31.

Abstract

The asymmetric borylation of N-tert-butanesulfinyl imines with bis(pinacolato)diboron is achieved using a Cu(II) catalyst and provides access to synthetically useful and pharmaceutically relevant α-amino boronic acid derivatives. The Cu(II)-catalyzed reaction is performed on the benchtop in air at room temperature using commercially available, inexpensive reagents at low catalyst loadings. A variety of N-tert-butanesulfinyl imines, including ketimines, react readily to provide α-sulfinamido boronate esters in good yields and with high stereoselectivity. In addition, this transformation is applied to the straightforward, telescoped synthesis of α-sulfinamido trifluoroborates.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Borates / chemical synthesis*
  • Boron Compounds / chemistry*
  • Boronic Acids / chemical synthesis*
  • Boronic Acids / chemistry
  • Butanones / chemistry*
  • Catalysis
  • Copper / chemistry*
  • Imines / chemistry*
  • Molecular Structure
  • Stereoisomerism
  • Sulfonamides / chemical synthesis*
  • Sulfonamides / chemistry

Substances

  • Borates
  • Boron Compounds
  • Boronic Acids
  • Butanones
  • Imines
  • Sulfonamides
  • bis(pinacolato)diboron
  • Copper
  • fluoroboric acid