Phosphorus oxychloride → 4-chloro-1-ethyl-3-nitro-1H-pyridin-2-one

HRID 2244804Notes

Reaction equation

HRID 2244804 reaction equation
[CH2:1]([N:3]1[CH:8]=[CH:7][C:6](O)=[C:5]([N+:10]([O-:12])=[O:11])[C:4]1=[O:13])[CH3:2].O=P(Cl)(Cl)[Cl:16]>>[Cl:16][C:6]1[CH:7]=[CH:8][N:3]([CH2:1][CH3:2])[C:4](=[O:13])[C:5]=1[N+:10]([O-:12])=[O:11]

Participants

3

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 714223361-Ethyl-4-hydroxy-3-nitropyridin-2(1H)-one

Product 1

HCID 714223354-chloro-1-ethyl-3-nitro-1H-pyridin-2-oneYield 53%

Procedure

A suspension of 1-ethyl-4-hydroxy-3-nitro-1H-pyridine-2-one (1.0 g, 5.43 mmol) in POCl3 (8.33 g, 54.3 mmol) was heated at refluxed for 1 h. After cooling to room temperature, the solvent was evaporated under reduced pressure and water was carefully added to the chilled residue. The mixture was neutralized with 2 N NaOH, extracted with CHCl3, washed with brine, dried over MgSO4 and concentrated under reduced pressure. The resulting solid was washed with Et2O to give 4-chloro-1-ethyl-3-nitro-1H-pyridin-2-one (0.58 g, 53% yield). 1H-NMR (CDCl3): δ 7.48 (d, 1H, J=7.6 Hz), 6.37 (d, 1H, J=7.6 Hz), 4.07 (q, 2H, J=7.2 Hz), 1.40 (t, 3H, J=7.2 Hz). MS: calculated for C7H7ClN2O3+H 203.0; found: 203.1.

Workup

  1. temperaturewas heated
  2. temperatureat refluxed for 1 h
  3. customthe solvent was evaporated under reduced pressure and water
  4. additionwas carefully added to the chilled residue
  5. extractionextracted with CHCl3
  6. washwashed with brine
  7. dry with materialdried over MgSO4
  8. concentrationconcentrated under reduced pressure
  9. washThe resulting solid was washed with Et2O

Sources & evidence

ORD record
ord-6d8568c8ab6f4f5e8b0a1e8424f47284
Source dataset
uspto-grants-2010_03
Patent number
US07678909B1

Reaction notes

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