Methyl (4S,5R)-5-[3, 4-(dimethylmethylenedioxy)phenyl]-2-phenyl-2-oxazoline-4-carboxylate → Droxidopa

Participants

Reaction Steps

Methyl (4S,5R)-5-[3, 4-(dimethylmethylenedioxy)phenyl]-2-phenyl-2-oxazoline-4-carboxylate (500 mg, 1.41 mmol) was added to 2N-hydrochloric acid (10 ml) with stirring at room temperature, and the mixture was then refluxed for 16 hours. After cooling to room temperature, about 25° C., the reaction mixture was concentrated under reduced pressure and neutralized with an aqueous 1N-sodium hydroxide solution to obtain a precipitated crystal. The precipitated crystal then was filtered to obtain 265 mg (1.24 mmol, yield: 88%) of L-threo DOPS.

Provenance & Evidence