Sulfuric Acid → 6-(trifluoromethyl)-1H-indazol-5-amine

Under ice-cooling, 1.01 g (12.0 mmol) of sodium nitrate was added to a mixture of 1.54 g (8.29 mmol) of 6-trifluoromethylindazole and 5 ml of concentrated sulfuric acid, and the mixture was stirred for 1 hour. The reaction mixture was poured onto ice and after ammonia water was added dropwise to the mixture under ice-cooling until pH reached 10 or higher, the precipitated solid was collected by filtration and then washed with water, followed by drying. The resulting crude product was dissolved in 50 ml of methanol, activated carbon was added to the mixture, and the mixture was filtered. 0.20 g of 5% Palladium-on-carbon was added to the filtrate, and the mixture was stirred under a hydrogen atmosphere at room temperature for 14 hours. The mixture was filtered through Celite and the filtrate was concentrated under reduced pressure to give 1.57 g (yield: 94%, two steps) of 5-amino-6-trifluoromethylindazole.

1. temperatureUnder ice-cooling
2. additionThe reaction mixture was poured onto ice
3. temperaturecooling until pH
4. filtrationhigher, the precipitated solid was collected by filtration
5. washwashed with water
6. customby drying
7. dissolutionThe resulting crude product was dissolved in 50 ml of methanol
8. additionactivated carbon was added to the mixture
9. filtrationthe mixture was filtered
10. addition0.20 g of 5% Palladium-on-carbon was added to the filtrate
11. stirringthe mixture was stirred under a hydrogen atmosphere at room temperature for 14 hours
12. filtrationThe mixture was filtered through Celite
13. concentrationthe filtrate was concentrated under reduced pressure

ORD 기록

ord-fe4bce7044bb4b86bfea569bdf17a5e4

출처 데이터셋

uspto-grants-2011_02

DOI

10.6084/m9.figshare.5104873.v1

특허 번호

US07879887B2