反应详情

温度

50 °C

28.7 g (0.1 mol) of 2,4-dichloro-4',5-difluorobenzophenone are dissolved in 250 g of 10% oleum, and 25 g of 50% hydrogen peroxide solution are added at temperatures up to 30° C. When the metered addition has ended (30 min), the mixture is heated for 8 h at 50° C. and, after cooling, is poured on to 250 g of ice. This mixture is kept for 8 h at 140° C. and 4-fluorophenol is then recovered by steam distillation (7.5 g, 0.0673 mol, 67%, m.p. (DSC) 42.6° C.). 2,4-dichloro-5-fluorobenzoic acid is isolated as described in Example 1 (17.0 g, 0.0813 mol, 81%, m.p. 143°-145° C.). (DSC =differential scanning calorimetry)

1. additionWhen the metered addition
2. custom(30 min)
3. temperatureafter cooling
4. distillation4-fluorophenol is then recovered by steam distillation (7.5 g, 0.0673 mol, 67%, m.p. (DSC) 42.6° C.)