Benzyl Bromide → 1-tert-Butyl 2-benzyl 5-oxopyrrolidine-1,2-dicarboxylate

HRID 1793449Notes

Reaction equation

HRID 1793449 reaction equation
[C:1]([O:5][C:6]([N:8]1[C:12](=[O:13])[CH2:11][CH2:10][C@H:9]1[C:14]([OH:16])=[O:15])=[O:7])([CH3:4])([CH3:3])[CH3:2].[CH2:17](Br)[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1.C(=O)([O-])[O-].[K+].[K+]>CN(C=O)C>[C:1]([O:5][C:6]([N:8]1[C:12](=[O:13])[CH2:11][CH2:10][CH:9]1[C:14]([O:16][CH2:17][C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1)=[O:15])=[O:7])([CH3:4])([CH3:2])[CH3:3]

Participants

5

Reactant 3

HCID 7498Benzyl BromideHCID 11430Potassium CarbonateHCID 1044121,2-Pyrrolidinedicarboxylic acid, 5-oxo-, 1-(1,1-dimethylethyl) ester, (2S)-

Product 1

HCID 138934141-tert-Butyl 2-benzyl 5-oxopyrrolidine-1,2-dicarboxylateYield 59.1%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
65 °C

Procedure

A suspension containing (2S)5-oxo-pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester (10.00 g, 0.044 mol, 1.0 equivalent), benzyl bromide (7.88 g, 0.046 mol, 1.05 equivalents), and potassium carbonate (15.20 g, 0.11 mol, 2.5 equivalents) in DMF (200 ml) was allowed to stir at 65° C. overnight. The reaction was allowed to cool to room temperature and the mixture was filtered through Celite. The solid was rinsed with ethyl acetate (100 ml) and the resulting filtrate was partitioned between ethyl acetate and saturated brine solution. The organic layer was washed with saturated brine (3×100 ml), dried over anhydrous Na2SO4 and concentrated in vacuo. The crude, colorless oil was chromatographed on silica to afford 5-oxo-pyrrolidine-1,2-dicarboxylic acid 2-benzyl ester 1-tert-butyl ester as a colorless oil (8.20 g, 0.026 mol, 59% yield). Analysis H1 NMR (400 MHz, CDCl3): 7.36 (5H, broad s), 5.20 (2H, d), 4.64 (1H, dd), 2.44–1.96 (4H, m), 1.41 (9H, s). MS (LC-MS): Calculated for C17H21NO5 319.14, found 320.19 (M+H)+.

Workup

  1. temperatureto cool to room temperature
  2. filtrationthe mixture was filtered through Celite
  3. washThe solid was rinsed with ethyl acetate (100 ml)
  4. customthe resulting filtrate was partitioned between ethyl acetate and saturated brine solution
  5. washThe organic layer was washed with saturated brine (3×100 ml)
  6. dry with materialdried over anhydrous Na2SO4
  7. concentrationconcentrated in vacuo
  8. customThe crude, colorless oil was chromatographed on silica

Sources & evidence

ORD record
ord-302383b5d1ae466490342ab67ce79b14
Source dataset
uspto-grants-2006_07
Patent number
US07081458B2

Reaction notes

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