반응 #9964

반응 방정식

benzoxazole

sulfuric acid

nitric acid

sulfuric acid

5-fluoro-2-methylbenzoxazole

→

5-Fluoro-2-Methyl-6-Nitrobenzoxazole

반응 조건

후처리

1. 1
   온도cooled in an ice/water bath
2. 2
   workup.WAITat such a rate that the temperature stayed at 15–20° C., over a 15–20 minute period
3. 3
   workup.ADDITIONWhen this acid solution had been added the cooling bath
4. 4
   기타was removed
5. 5
   workup.ADDITIONAt the end of this period the solution was carefully poured onto ice with good stirring
6. 6
   workup.ADDITIONSufficient water was then added
7. 7
   기타to get good mixing
8. 8
   여과The solid was filtered off
9. 9
   세척washed well with water
10. 10
    기타air-dried

실험 절차

Concentrated sulfuric acid (60 mL) was stirred mechanically and cooled in an ice/water bath. To this was gradually added 5-fluoro-2-methylbenzoxazole (9), (20 g, 0.132 Moles), at such a rate that the temperature stayed at 15–20° C., over a 15–20 minute period. A solution of concentrated sulfuric acid (11 mL), and concentrated nitric acid (10 mL), was prepared and added drop by drop to the benzoxazole solution at such a rate that the temperature was maintained at approximately 10° C. When this acid solution had been added the cooling bath was removed and the mixture allowed to stir at room temperature for 1 hour. At the end of this period the solution was carefully poured onto ice with good stirring. Sufficient water was then added to get good mixing. The solid was filtered off, washed well with water and air-dried. Yield 16.0 g.

출처