Valeryl chloride → (S)-4-benzyl-3-pentanoyloxazolidin-2-one

HRID 2422341Notes

Reaction equation

HRID 2422341 reaction equation
[CH2:1]([C@H:8]1[CH2:12][O:11][C:10](=[O:13])[NH:9]1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C([Li])CCC.[C:19](Cl)(=[O:24])[CH2:20][CH2:21][CH2:22][CH3:23]>C1COCC1.[NH4+].[Cl-].C(OCC)(=O)C>[CH2:1]([C@H:8]1[CH2:12][O:11][C:10](=[O:13])[N:9]1[C:19](=[O:24])[CH2:20][CH2:21][CH2:22][CH3:23])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

7

Reactant 3

HCID 61186Valeryl chlorideHCID 736225(S)-4-Benzyl-2-oxazolidinoneHCID 178418339Butyllithium

Product 1

HCID 11391341(S)-4-benzyl-3-pentanoyloxazolidin-2-oneYield 99.1%

Reagents, catalysts & solvents 3

HCID 8028TetrahydrofuranSolventHCID 8857Ethyl AcetateSolventHCID 25517Ammonium ChlorideSolvent

Procedure

A solution of 4(S)-(−)-benzyl-2-oxazolidinone (10 g, 56.43 mmol) in anhydrous THF (200 ml) at −78° C. was treated with a 2.5M solution of n-butyl lithium in hexanes (23.70 ml, 59.26 mmol) with stirring. The reaction mixture was allowed to stir at −78° C. for 30 min before valeryl chloride (7.57 ml, 62.10 mmol) was added. The reaction mixture was then allowed to warm to ambient temperature over 15 h after which it was diluted with NH4Cl solution, diluted with ethyl acetate and washed with brine. The organic phase was dried (Na2SO4) and concentrated to give a gum. This was purified by flash chromatography (10% EtOAc in 40/60 hexanes) to give the sub-title compound (14.61 g, 99%) as a colourless oil: 1H NMR (400 MHz, CDCl3) δ 0.94-1.20 (3H, m), 1.35-1.50 (2H, m), 1.62-1.80 (2H, m), 2.74-2.84 (1H, m), 2.86-3.08 (2H, m), 3.27-3.39 (1H, m), 4.11-4.26 (2H, m), 4.62-4.76 (1H, m), 7.18-7.40 (5H, m).

Workup

  1. additionwas added
  2. washwashed with brine
  3. dry with materialThe organic phase was dried (Na2SO4)
  4. concentrationconcentrated
  5. customto give a gum
  6. customThis was purified by flash chromatography (10% EtOAc in 40/60 hexanes)

Sources & evidence

ORD record
ord-a4ebd9599c0a40d7ab1a50eae391414b
Source dataset
uspto-grants-2011_06
Patent number
US07960398B2

Reaction notes

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