反应详情

温度

80 °C

The compound (1.2 g) obtained in Step 3 was suspended in 2N aqueous sodium hydroxide solution (18 ml) and, under ice-cooling, sodium nitrite (1.2 g) was added in several portions. The obtained suspension was slowly added dropwise to a concentrated aqueous hydrochloric acid solution (18 ml) heated to 80° C., and the mixture was stirred at the same temperature for 1 hr. The reaction mixture was cooled to room temperature, and the precipitated solid was collected by filtration, washed with water and dried to give the title compound (0.60 g). The filtrate was extracted with ethyl acetate, and the organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, filtrated, and concentrated under reduced pressure to give a crude product (0.34 g) containing the title compound as a main component. The obtained crude crystals were suspended in a mixed solvent of hexane and ethyl acetate, collected by filtration and dried to give the title compound (0.26 g).

1. temperaturecooling
2. temperatureThe reaction mixture was cooled to room temperature
3. filtrationthe precipitated solid was collected by filtration
4. washwashed with water
5. customdried