Methanol → (-)-N-Acetylphenylalanine

HRID 267307Notes

Reaction equation

HRID 267307 reaction equation
[C:1]([NH:4][C@@H:5]([C:13]([OH:15])=[O:14])[CH2:6][C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1)(=[O:3])[CH3:2].[CH3:16][O:17][C:18](=[O:28])[CH:19]([CH2:21][C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1)[NH2:20].CO>O>[C:1]([NH:4][C@@H:5]([C:13]([OH:15])=[O:14])[CH2:6][C:7]1[CH:8]=[CH:9][CH:10]=[CH:11][CH:12]=1)(=[O:3])[CH3:2].[CH3:16][O:17][C:18](=[O:28])[C@H:19]([CH2:21][C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1)[NH2:20]

Participants

6

Reactant 3

HCID 887MethanolHCID 75737DL-Phenylalanine, methyl esterHCID 101184(-)-N-Acetylphenylalanine

Product 2

HCID 101184(-)-N-AcetylphenylalanineHCID 736234L-Phenylalanine, methyl ester

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

Typically, N-acetyl-D-phenylalanine is allowed to contact DL-phenylalanine methyl ester in a suitable solvent, e.g. methanol or water, to produce a crystalline salt of N-acetyl-D-phenylalanine and L-phenylalanine methyl ester. That salt is separated from the filtrate and decomposed with aqueous hydrochloric acid to afford N-acetyl-D-phenylalanine as a precipitate and L-phenylalanine methyl ester hydrochloride in solution. After filtering, the solvent in the filtrate is removed to afford the hydrochloride salt of L-phenylalanine methyl ester. Alternatively, the salt of N-acetyl-D-phenylalanine and L-phenylalanine methyl ester is dissolved in aqueous potassium carbonate and extracted with ether. The D-amide remains in the aqueous phase and the L-ester remains in the organic phase. After phase separation, the ethereal solution is acidified with hydrochloric acid-isopropanol to precipitate the hydrochloride salt of L-phenylalanine methyl ester.

Sources & evidence

ORD record
ord-6cebd62a41834132bba35f68a27a8b21
Source dataset
uspto-grants-1976_03
Patent number
US03941831

Reaction notes

Loading…