Urea → 2-Tert-butyl-5-nitrophenol

HRID 401301

反応式

HRID 401301 の反応式
[C:1]([C:5]1[CH:11]=[CH:10][C:9]([N+:12]([O-:14])=[O:13])=[CH:8][C:6]=1N)([CH3:4])([CH3:3])[CH3:2].N([O-])=[O:16].[Na+].NC(N)=O.OS(O)(=O)=O.O>OS(O)(=O)=O.O>[C:1]([C:5]1[CH:11]=[CH:10][C:9]([N+:12]([O-:14])=[O:13])=[CH:8][C:6]=1[OH:16])([CH3:4])([CH3:3])[CH3:2]

参加物

7

反応条件

温度
2.5 °C

実験手順

To a mixture of 2-tert-butyl-5-nitroaniline (1.94 g, 10 mmol) in 40 mL of 15% H2SO4 was added dropwise a solution of NaNO2 (763 mg, 11.0 mmol) in water (3 mL) at 0° C. The resulting mixture was stirred at 0-5° C. for 5 min. Excess NaNO2 was neutralized with urea, then 5 mL of H2SO4—H2O (v/v 1:2) was added and the mixture was refluxed for 5 min. Three additional 5 mL aliquots of H2SO4—H2O (v/v 1:2) were added while heating at reflux. The reaction mixture was cooled to room temperature and extracted with EtOAc twice. The combined organic layers were washed with brine and dried over MgSO4. After removal of solvent, the residue was purified by column chromatography (0-10% EtOAc-Hexane) to give 2-tert-butyl-5-nitrophenol (C-1-a) (1.2 g, 62%). 1H NMR (400 MHz, CDCl3) δ 7.76 (dd, J=8.6, 2.2 Hz, 1H), 7.58 (d, J=2.1 Hz, 1H), 7.43 (d, J=8.6 Hz, 1H), 5.41 (s, 1H), 1.45 (s, 9H); HPLC ret. time 3.46 min, 10-99% CH3CN, 5 min run.

後処理

  1. temperaturethe mixture was refluxed for 5 min
  2. temperaturewhile heating
  3. temperatureat reflux
  4. temperatureThe reaction mixture was cooled to room temperature
  5. extractionextracted with EtOAc twice
  6. washThe combined organic layers were washed with brine
  7. dry with materialdried over MgSO4
  8. customAfter removal of solvent
  9. customthe residue was purified by column chromatography (0-10% EtOAc-Hexane)

出典と根拠

ORDレコード
ord-6149daed63604e4e8b4ffc5776674110
出典データセット
uspto-grants-2014_06
特許番号
US08741925B2

関連ノート

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