反应详情

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.

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