Reaktion #161149

Reaktionsgleichung

urea

H2SO4 H2O

NaNO2

NaNO2

H2SO4 H2O

2-tert-butyl-5-nitroaniline

→

2-tert-butyl-5-nitrophenol

Ausbeute 62.0%

Lösungsmittel

water

H2SO4

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe mixture was refluxed for 5 min
2. 2
   Temperaturwhile heating
3. 3
   Temperaturat reflux
4. 4
   TemperaturThe reaction mixture was cooled to room temperature
5. 5
   Extraktionextracted with EtOAc twice
6. 6
   WaschenThe combined organic layers were washed with brine
7. 7
   Trocknendried over MgSO4
8. 8
   SonstigeAfter removal of solvent
9. 9
   Sonstigethe residue was purified by column chromatography (0-10% EtOAc-Hexane)

Vorschrift

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.

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