Base-catalyzed isomerization of 2-isoxazolines enables a two-step enantioselective synthesis of β-hydroxynitriles from enals.
The asymmetric synthesis of β-hydroxynitriles remains a challenge in organic synthesis. Herein we report a convenient synthesis of β-hydroxynitriles from enantiomerically enriched 3-unsubstituted 2-isoxazolines via a base-catalyzed ring-opening reaction that takes place without loss of enantiopurity. In combination with organocatalytic enantioselective synthesis of 3-unsubstituted 2-isoxazolines, the ring-opening enables a short 2-step synthesis of β-hydroxynitriles from α,β-unsaturated aldehydes in high enantiomeric purity.
Pohjakallio
Antti
A
Department of Chemistry, Aalto University School of Science and Technology, Kemistintie 1, FI-02150 Espoo, Finland.
Pihko
Petri M
PM
Liu
Jun
J
D000447:Aldehydes / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D005021:Ethylamines / Q000737:chemistry*; D007555:Isoxazoles / Q000737:chemistry*; D015394:Molecular Structure; D009570:Nitriles / Q000737:chemistry; D013237:Stereoisomerism
D000447:Aldehydes; D005021:Ethylamines; D007555:Isoxazoles; D009570:Nitriles; C016162:triethylamine