Hydrochloric Acid → Droxidopa

Participants

Reaction Steps

Methyl (4S,5R)-5-(3,4-dibenzyloxyphenyl)-2-phenyl-2-oxazoline-4-carboxylate (157 mg, 0.50 mmol), was added to 1N-hydrochloric acid (5 ml) with stirring, and the mixture was refluxed for 17 hours. After cooling to room temperature, the reaction mixture was washed with ether and neutralized with 1N sodium hydroxide to obtain precipitated crystals. The precipitated crystal then was filtered to obtain 76 mg (0.36 mmol, yield: 71%) of L-threo DOPS.

Provenance & Evidence