反应详情

24 g of 2,4-Difluoro-5-nitrophenol, dissolved in 120 ml of methanol, are subjected to hydrogenation at a hydrogen pressure of 20-40 bar at 25°-45° C. in the presence of 2 g of Raney nickel. When constant pressure is reached (i.e. when the take-up of hydrogen is complete), the pressure is released and the mixture is cooled, the solution is free from catalyst by filtration, and the methanol is subsequently removed by distillation at reduced pressure. 18 g (GC purity 97.5%) of 2,4-difluoro-5-aminophenol are obtained.

1. temperaturethe mixture is cooled
2. filtrationthe solution is free from catalyst by filtration
3. customthe methanol is subsequently removed by distillation at reduced pressure