反应详情

温度

20 °C

To a solution of 60 mL of hydrazine monohydrate in 380 mL of ethanol was added 81 g (0.38 mole) of 2,3-dichloro-5-trifluoromethylpyridine during a period of 25 minutes. At the end of the addition the temperature had risen to 37° C. This mixture was heated to reflux and maintained at reflux for approximately 15 hours. The solvent was evaporated under reduced pressure, leaving a wet slurry that was immediately recrystallized from boiling ethanol/water (5:2). The mixture was cooled to 20° C. and then filtered. The filter cake was air-dried, yielding approximately 60 g of 3-chloro-5-trifluoromethylpyrid-2-ylhydrazine. The NMR spectrum was consistent with the assigned structure. This reaction was repeated to obtain additional material for subsequent reactions.

1. additionAt the end of the addition the temperature
2. customhad risen to 37° C
3. temperatureThis mixture was heated
4. temperatureto reflux
5. temperaturemaintained
6. temperatureat reflux for approximately 15 hours
7. customThe solvent was evaporated under reduced pressure
8. customleaving a wet slurry that
9. customwas immediately recrystallized
10. filtrationfiltered
11. customThe filter cake was air-dried