Chiral Integrated Catalysts Composed of Bifunctional Thiourea and Arylboronic Acid: Asymmetric Aza-Michael Addition of α,β-Unsaturated Carboxylic Acids

Chem Pharm Bull (Tokyo). 2016;64(7):704-17. doi: 10.1248/cpb.c15-00983.

Abstract

The first intermolecular asymmetric Michael addition of nitrogen-nucleophiles to α,β-unsaturated carboxylic acids was achieved through a new type of arylboronic acid equipped with chiral aminothiourea. The use of BnONH2 as a nucleophile gives a range of enantioenriched β-(benzyloxy)amino acid derivatives in good yields and with high enantioselectivity (up to 90% yield, 97% enantiomeric excess (ee)). The obtained products are efficiently converted to optically active β-amino acid and 1,2-diamine derivatives.

MeSH terms

  • Amino Acids / chemical synthesis*
  • Amino Acids / chemistry
  • Aza Compounds / chemistry*
  • Boronic Acids / chemistry*
  • Carboxylic Acids / chemistry*
  • Catalysis
  • Molecular Structure
  • Stereoisomerism
  • Thiourea / chemistry*

Substances

  • Amino Acids
  • Aza Compounds
  • Boronic Acids
  • Carboxylic Acids
  • Thiourea