反应 #501395

反应方程式

3,6-dichloropyridazine

ammonium hydroxide

sulfuric acid

ammonium persulfate

pivalic acid

→

3,6-dichloro-4-t-butylpyridazine

溶剂

water

water

反应条件

后处理

1. 1
   温度the mixture was heated to 62°
2. 2
   workup.ADDITIONTo it was added 1 kg
3. 3
   其他was controlled at 80°
4. 4
   workup.ADDITIONAfter the addition
5. 5
   温度was then cooled to 15° with an ice-water bath
6. 6
   温度The mixture was then cooled further by the addition of ice, and its pH
7. 7
   workup.STIRRINGIt was then stirred vigorously for 1 hour, while gummy material
8. 8
   过滤It was then filtered
9. 9
   洗涤the solids were washed with 2 liters of water
10. 10
    其他dried on the filter pad
11. 11
    过滤the slurry was filtered
12. 12
    洗涤The filtrate was washed three times with 500 ml
13. 13
    萃取extracted with 500 ml
14. 14
    洗涤was washed with 500 ml
15. 15
    干燥The organic layer was dried over magnesium sulfate and carbon
16. 16
    workup.ADDITIONtreated at the reflux temperature
17. 17
    温度It was then cooled
18. 18
    过滤filtered through diatomaceous earth
19. 19
    其他the filtrate was evaporated under vacuum
20. 20
    其他to obtain 449 g

实验过程

A 375 g. portion of 3,6-dichloropyridazine was slurried with 578 g. of pivalic acid in 367 g. of sulfuric acid and 1500 ml. of water, and the mixture was warmed to 40°. Then 48.2 g. of silver nitrate was added, and the mixture was heated to 62°. To it was added 1 kg. of ammonium persulfate in 2 liters of water over a period of 1 hour. The temperature rose exothermically, and was controlled at 80° maximum. After the addition, the mixture was stirred for 15 minutes, and was then cooled to 15° with an ice-water bath. The mixture was then cooled further by the addition of ice, and its pH was adjusted to 9 with ammonium hydroxide. It was then stirred vigorously for 1 hour, while gummy material was scraped from the sides of the vessel as needed. It was then filtered, and the solids were washed with 2 liters of water and dried on the filter pad. The solids were then slurried in 5 liters of diethyl ether and the slurry was filtered. The filtrate was washed three times with 500 ml. portions of 1N sodium hydroxide, and the washes were combined and extracted with 500 ml. of diethyl ether. That ether was combined with the first ether filtrate, and was washed with 500 ml. of brine. The organic layer was dried over magnesium sulfate and carbon treated at the reflux temperature. It was then cooled and filtered through diatomaceous earth, and the filtrate was evaporated under vacuum to obtain 449 g. of the desired intermediate.

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