反应详情

温度

50 °C

To an ice-cold solution of 2-amino-3-bromo-5-nitro-phenol (6.50 g, 27.89 mmol) in EtOH (150.0 mL) was added concentrated H2SO4 (9.40 mL, 177.13 mmol) portion wise. The reaction mixture was then heated to 50° C. followed by portion wise addition of NaNO2 (6.19 g, 89.82 mmol). The resulting solution was refluxed at 80° C. for 2 h. The reaction mixture was then diluted with water and extracted with EtOAc (3×150.0 mL). The combined organics was dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude was purified over silica gel (100-200 M, 10% EtOAc-Hexane) to get the desired product (5.0 g, 82%).

1. temperatureThe resulting solution was refluxed at 80° C. for 2 h
2. extractionextracted with EtOAc (3×150.0 mL)
3. dry with materialThe combined organics was dried over anhydrous Na2SO4
4. concentrationconcentrated under reduced pressure
5. customThe crude was purified over silica gel (100-200 M, 10% EtOAc-Hexane)