反应详情

温度

0 °C

A solution of KNO3 (3.38 g, 33.4 mmol) in 96% aqueous H2SO4 (30 ml) was added to a solution of 4-bromothiophene-2-carbaldehyde (5.8 g, 30.4 mmol) in 96% aqueous H2SO4 (60 ml) over 45 minutes, maintaining the temperature below 4° C. The resulting mixture was stirred at 0° C. for 2 hrs and then at RT overnight. The reaction was poured into ice (300 ml) and the resulting precipitate was filtered and washed with water and hexane to afford 4-bromo-5-nitrothiophene-2-carbaldehyde (Int. 65) (6.987 g, 29.6 mmol).

1. temperaturemaintaining the temperature below 4° C
2. customat RT
3. customovernight
4. filtrationthe resulting precipitate was filtered
5. washwashed with water and hexane