Dimethylformamide → Boc-L-phenylalanine methyl ester

HRID 617636Notes

Reaction equation

HRID 617636 reaction equation
[C:1]([O:5][C:6]([NH:8][C@H:9]([C:17]([OH:19])=[O:18])[CH2:10][C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1)=[O:7])([CH3:4])([CH3:3])[CH3:2].[C:20](=O)([O-])O.[K+].CN(C)C=O.CI>O>[CH3:20][O:18][C:17](=[O:19])[C@H:9]([CH2:10][C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1)[NH:8][C:6]([O:5][C:1]([CH3:4])([CH3:2])[CH3:3])=[O:7]

Participants

6

Reactant 4

HCID 6228DimethylformamideHCID 6328Methyl iodideHCID 77857L-Phenylalanine, N-[(1,1-dimethylethoxy)carbonyl]-HCID 516893Potassium Bicarbonate

Product 1

HCID 9882138Boc-L-phenylalanine methyl esterYield 97.4%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

To a mixture of N-tert-butoxycarbonylphenylalanine (13.3 g, 50.0 mmol), potassium hydrogencarbonate (10.0 g, 100 mmol) and N,N-dimethylformamide (80 mL) was added methyl iodide (5 mL, 80 mmol). The resulting mixture was stirred at room temperature for 5 h, and water (200 mL) was added. The mixture was extracted with ethyl acetate-benzene (1:1), and the organic layer was washed successively with water, 5% aqueous sodium sulfite solution and saturated brine, and dried over anhydrous sodium sulfate. The solvent was evaporated and the obtained residue was separated and purified by silica gel column chromatography (hexane-ethyl acetate, 90:10) to give 13.6 g (96%) of N-tert-butoxycarbonylphenylalanine methyl ester as a colorless oil.

Workup

  1. extractionThe mixture was extracted with ethyl acetate-benzene (1:1)
  2. washthe organic layer was washed successively with water, 5% aqueous sodium sulfite solution and saturated brine
  3. dry with materialdried over anhydrous sodium sulfate
  4. customThe solvent was evaporated
  5. customthe obtained residue was separated
  6. custompurified by silica gel column chromatography (hexane-ethyl acetate, 90:10)

Sources & evidence

ORD record
ord-7bd697ad834a46c4a5ca553acd29ef1c
Source dataset
uspto-grants-1999_09
Patent number
US05948785

Reaction notes

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