L-Phenylalanine → (2S)-2-[(4-methoxyphenyl)methoxycarbonylamino]-3-phenylpropanoic acid

L-Phenylalanine (330 mg.) and sodium bicarbonate (202 mg.) were dissolved in water (10 ml.) under heating and allowed to stand. A solution of diethyl 2-(4-methoxybenzyloxycarbonyloxyimino)malonate (1.0 g.) in tert-butyl alcohol (10 ml.) was added to the solution with stirring at room temperature and water (10 ml.) was added thereto. The mixture was then stirred for 2 hours at room temperature. The reaction mixture was brought to pH 9 by adding water (20 ml.) and a saturated sodium bicarbonate aqueous solution (10 ml.), and water (10 ml.) was added thereto. The resulting mixture was then washed twice with ethyl acetate (20 ml.). The aqueous layer was adjusted to pH 7 with a 10% citric acid aqueous solution, washed twice with ethyl acetate (30 ml.), adjusted to pH 3.5 with a 10% citric acid aqueous solution and extracted three times with ethyl acetate (30 ml.). The extract was washed with a sodium chloride aqueous solution and dried over magnesium sulfate. The solvent was distilled off under reduced pressure to give N-(4-methoxybenzyloxycarbonyl)-L-phenylalanine (410 mg.), oil.

1. temperatureunder heating
2. stirringThe mixture was then stirred for 2 hours at room temperature
3. washThe resulting mixture was then washed twice with ethyl acetate (20 ml.)
4. washwashed twice with ethyl acetate (30 ml.)
5. extractionextracted three times with ethyl acetate (30 ml.)
6. washThe extract was washed with a sodium chloride aqueous solution
7. dry with materialdried over magnesium sulfate
8. distillationThe solvent was distilled off under reduced pressure

ORD record

ord-b40aa76426924fbfbc762ec812ebe95f

Source dataset

uspto-grants-1978_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04083848