Methanol → Methyl L-phenylalaninate hydrochloride

HRID 553063Notes

Reaction equation

HRID 553063 reaction equation
S(Cl)([Cl:3])=O.[NH2:5][C@H:6]([C:14]([OH:16])=[O:15])[CH2:7][C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1.[CH3:17]O>>[ClH:3].[CH3:17][O:15][C:14](=[O:16])[C@H:6]([CH2:7][C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1)[NH2:5]

Participants

4

Reactant 3

HCID 887MethanolHCID 6140L-PhenylalanineHCID 24386Thionyl Chloride

Product 1

HCID 75736Methyl L-phenylalaninate hydrochloride

Procedure

Thionyl chloride (3.10 mL, 42.38 mmol, 1.4 eq) was added dropwise to a suspension of L-phenylalanine (5.0 g, 30.27 mmol, 1.0 eq) in dry MeOH (30 mL) at 0° C. The cold bath was removed and the solution was stirred at room temperature for 24 h, then concentrated under vacuum. The residue was triturated with cold Et2O, filtered and wash with cold Et2O and the filtrate evaporated in vacuo to give the L-phenylalanine methyl ester hydrochloride as a white crystalline solid in quantitative yield; IR (KBr) ν 1740 (CO), 3305 (NH) cm−1; 1H NMR (300 MHz, CDCl3) δH 1.46 (2H, s, —NH2), 2.75 (1H, dd, J=6.8 and 14.1 Hz, —CHαPh), 3.00 (1H, dd, J=6.7 and 14.2 Hz, —CHβPh), 3.72 (3H, s, OMe), 4.65 (1H, t, J=6.8 Hz, —CH—) and 7.10-7.30 (5H, m, Ar—H), which was sufficiently pure and used directly in the next step.

Workup

  1. customThe cold bath was removed
  2. concentrationconcentrated under vacuum
  3. customThe residue was triturated with cold Et2O
  4. filtrationfiltered
  5. washwash with cold Et2O
  6. customthe filtrate evaporated in vacuo

Sources & evidence

ORD record
ord-c74f7c011c444266bbf9cf1ad1254548
Source dataset
uspto-grants-2011_05
Patent number
US07951834B2

Reaction notes

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