Water → L-Phenylalanine, methyl ester

HRID 990125Notes

Reaction equation

HRID 990125 reaction equation
[CH3:1][O:2][C:3](=[O:29])[C@H:4]([CH2:19][C:20]1[CH:25]=[CH:24][C:23]([N+]([O-])=O)=[CH:22][CH:21]=1)[NH:5]C(C1(CCNC(=O)C)CCCC1)=S.O.ClCCl.CC(C)=O>CO.C(OCC)(=O)C.[Cl-].[NH4+].[Zn]>[CH3:1][O:2][C:3](=[O:29])[C@H:4]([CH2:19][C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1)[NH2:5]

Participants

8

Reactant 3

HCID 962WaterHCID 12042588HCID 12042588, compoundHCID 21584124Propan-2-one--dichloromethane (1/1)

Product 1

HCID 736234L-Phenylalanine, methyl esterYield 207.3%

Reagents, catalysts & solvents 4

HCID 23994ZincCatalystHCID 887MethanolSolventHCID 8857Ethyl AcetateSolventHCID 25517Ammonium ChlorideSolvent2×

Procedure

To a suspension of N-[[1-[2-(acetylamino)ethyl]cyclopentyl]thioxomethyl]-4-nitro-L-phenylalanine methyl ester (740 mg, 1.75 mmol), zinc dust (1.14 g, 17.5 mmol) and ammonium chloride (1.41 g, 26.3 mmol) in methanol (20 mL) was added H2O (10 mL) slowly over 5 min. After stirring for 20 min, the reaction mixture was diluted with ethyl acetate (80 mL) and sat. ammonium chloride solution (25 mL). The separated aqueous layer was back-extracted with ethyl acetate (3×25 mL) and the organic layers were combined, dried over Na2SO4, filtered and concentrated in vacuo. The residual oil was dried under high vacuum for 2 h to give the crude amine (750 mg)which was by flash silica gel column chromatography (dichloromethane-acetone 2:1) to furnish 4-amino-N-[[1-[2-acetylamino)ethyl]cyclopentyl]thioxomethyl]-L-phenylalanine methyl ester (650 mg, 95%). HR MS: Obs. mass, 392.2016. Calcd. mass, 392.2008 (M+H).

Workup

  1. extractionThe separated aqueous layer was back-extracted with ethyl acetate (3×25 mL)
  2. dry with materialdried over Na2SO4
  3. filtrationfiltered
  4. concentrationconcentrated in vacuo
  5. customThe residual oil was dried under high vacuum for 2 h
  6. customto give the crude amine (750 mg)which

Sources & evidence

ORD record
ord-7055e77b00fd45e89180328222296b78
Source dataset
uspto-grants-2002_10
Patent number
US06458844B2

Reaction notes

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