反应详情

温度

20 °C

290 g (2.20 mol) of 3-methylindazole and an acetonitrile solution (400 ml) of pyridine (4.34 mol) were stirred as the mixture was cooled on a water bath, and 310 ml (3.30 mol) of acetic anhydride was added dropwise thereto. Upon addition, the reaction temperature rose from 15° C. to 43° C. After the conclusion of the dropwise addition, the reaction solution was warmed to from 55° to 60° C., and stirred at this temperature for one hour. After cooling to 20° C., the reaction solution was poured into 1.5 kg of ice-cold water containing 500 ml of aqueous hydrochloric acid. The crystals deposited were filtered off, and washed with water. Thus, 328 g (1.89 mol) of 1-acetyl-3-methylindazole was obtained.

1. temperaturewas cooled on a water bath
2. additionUpon addition
3. customrose from 15° C. to 43° C
4. additionAfter the conclusion of the dropwise addition
5. temperaturethe reaction solution was warmed to from 55° to 60° C.
6. filtrationThe crystals deposited were filtered off
7. washwashed with water