Chiral phosphoric acid-catalyzed enantioselective transfer hydrogenation of ortho-hydroxyaryl alkyl N-H ketimines.
Résumé
The first enantioselective chiral phosphoric acid-catalyzed transfer hydrogenation of unprotected ortho-hydroxyaryl alkyl N-H ketimines using Hantszch di-tert-butyl ester as a reductant is reported. A variety of ortho-hydroxybenzylamines were obtained in good to excellent yields and enantiomeric excesses.