Sodium Carbonate → (4S,5R)-4-(3,4-difluorophenyl)-2-oxo-oxazolidine-5-carboxylic acid methyl ester

HRID 1856659Notes

Reaction equation

HRID 1856659 reaction equation
[CH3:1][O:2][C:3](=[O:16])[C@H:4]([OH:15])[C@@H:5]([NH2:14])[C:6]1[CH:11]=[CH:10][C:9]([F:12])=[C:8]([F:13])[CH:7]=1.C(N(CC)C(C)C)(C)C.Cl[C:27](Cl)([O:29]C(=O)OC(Cl)(Cl)Cl)Cl.C(=O)([O-])[O-].[Na+].[Na+]>O1CCCC1.C(OCC)(=O)C>[CH3:1][O:2][C:3]([C@@H:4]1[O:15][C:27](=[O:29])[NH:14][C@H:5]1[C:6]1[CH:11]=[CH:10][C:9]([F:12])=[C:8]([F:13])[CH:7]=1)=[O:16]

Participants

7

Conditions

Temperature
0 °C

Procedure

To a solution of (2R,3S)-3-amino-3-(3,4-difluorophenyl)-2-hydroxypropionic acid methyl ester (5.8 g, 25 mmol) in 250 mL tetrahydrofuran at 0° C. was added N,N-diisopropylethylamine (8.75 mL, 50 mmol) and triphosgene (2.48 g, 8.4 mmol). The reaction was stirred at 0° C. for 30 min when it was poured over ethyl acetate (200 mL) and saturated sodium carbonate solution (100 mL). The layers were separated, the organic layer washed with saturated sodium carbonate solution (1×100 mL), dried with magnesium sulfate, and concentrated in vacuo to provide a pale yellow oil. The material was triturated with 25% ethyl acetate/hexane from dichloromethane to provide (4S,5R)-4-(3,4-difluorophenyl)-2-oxo-oxazolidine-5-carboxylic acid methyl ester. The recovered mother liqour was passed through silica (50% ethyl acetate/hexane) to give an additional 1.1 g (4.8 g total, 18 mmol, 75%)

Workup

  1. customThe layers were separated
  2. washthe organic layer washed with saturated sodium carbonate solution (1×100 mL)
  3. dry with materialdried with magnesium sulfate
  4. concentrationconcentrated in vacuo
  5. customto provide a pale yellow oil
  6. customThe material was triturated with 25% ethyl acetate/hexane from dichloromethane

Sources & evidence

ORD record
ord-f13a0cd1a1f9429c93dc8e027e916c41
Source dataset
uspto-grants-2000_11
Patent number
US06143750

Reaction notes

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