- Stereoselective synthesis of norephedrine and norpseudoephedrine by using asymmetric transfer hydrogenation accompanied by dynamic kinetic resolution.
Stereoselective synthesis of norephedrine and norpseudoephedrine by using asymmetric transfer hydrogenation accompanied by dynamic kinetic resolution.
The Journal of organic chemistry (2012-05-25)
Hyeon-Kyu Lee, Soyeong Kang, Eun Bok Choi
PMID22621372
ABSTRACT
Each of the enantiomers of both norephedrine and norpseudoephedrine were stereoselectively prepared from the common, prochiral cyclic sulfamidate imine of racemic 1-hydroxy-1-phenyl-propan-2-one by employing asymmetric transfer hydrogenation (ATH) catalyzed by the well-defined chiral Rh-complexes, (S,S)- or (R,R)-Cp*RhCl(TsDPEN), and HCO(2)H/Et(3)N as the hydrogen source. The ATH processes are carried out under mild conditions (rt, 15 min) and are accompanied by dynamic kinetic resolution.
MATERIALS
Product Number
Brand
Product Description
Supelco
(+)-Norpseudoephedrine hydrochloride solution, 100 μg/mL in methanol (as free base), ampule of 1 mL, certified reference material, Cerilliant®
Supelco
(±)-Phenylpropanolamine hydrochloride solution, 1.0 mg/mL in methanol (as free base), ampule of 1 mL, certified reference material, Cerilliant®