反应详情

温度

55 °C

A stirred suspension of 105 g (0.429 mole) of 2-amino-benzoic acid N′-(2-fluoro-phenyl)-hydrazide in 1250 mL of ethanol and 1250 mL of 1N hydrochloric acid was heated to 55° C. A solution of 59 g (0.858 mole) of sodium nitrite in 200 mL of water was added dropwise over a 30 minute period. Approximately 10 minutes into the addition a solid began separating. External heating was continued until the reaction temperature reached 65° C. and then it was turned off. The temperature remained at 65-68° C. during the addition and gas evolution became vigorous approximately halfway through the addition. Toward the end of the addition, gas evolution slowed and the temperature dropped below 65° C. External heating was reapplied and the mixture was stirred at 70° C. for 3 hours. The mixture was cooled to −10° C. and filtered. The solid was rinsed once with 50 mL of ethanol, then once with 100 mL of water, and pressed dry under suction. Further drying in vacuo at 35° C. for 7 hours afforded 92 g (94%) of product.

1. additionApproximately 10 minutes into the addition a solid
2. custombegan separating
3. temperatureExternal heating
4. customreached 65° C.
5. additionThe temperature remained at 65-68° C. during the addition and gas evolution
6. additionthrough the addition
7. additionToward the end of the addition, gas evolution
8. additionthe temperature dropped below 65° C
9. temperatureExternal heating
10. temperatureThe mixture was cooled to −10° C.
11. filtrationfiltered
12. washThe solid was rinsed once with 50 mL of ethanol
13. dry with materialonce with 100 mL of water, and pressed dry under suction
14. customFurther drying in vacuo at 35° C. for 7 hours