Sulfuric Acid → 3-Bromo-4-(trifluoromethoxy)aniline

Temperatur

80 °C

4-Trifluoromethoxynitrobenzene (4.1 g) was suspended in water (16 ml) and concentrated sulfuric acid (16 ml) and warmed to 80° C. with stirring. Potassium bromate (3.7 g) was added portionwise over 3 hours. The resulting mixture was heated at 80° C. for a further 2 hours, cooled to room temperature and poured onto ice (100 g). The mixture was extracted with ethyl acetate, dried (MgSO4), filtered, and the solvent removed in vacuo. The recovered solid (1.0 g) was taken up in acetic acid (2.5 ml) and water (10 ml) and iron powder (2.0 g) added. The resulting mixture was warmed to reflux for 2 hours, cooled to room temperature and filtered through Celite™. The filtrate was extracted with ethyl acetate, the organic layers separated, dried (MgSO4), filtered and the solvent removed in vacuo. Chromatography on silica gel (ethyl acetate:hexane 1:3) afforded the title compound as a yellow oil. 1H NMR (CDCl3) δ6.57 (1H, dd), 6.9 (1H, d), 7.06 (1H, dd).

1. temperaturecooled to room temperature
2. additionpoured onto ice (100 g)
3. extractionThe mixture was extracted with ethyl acetate
4. dry with materialdried (MgSO4)
5. filtrationfiltered
6. customthe solvent removed in vacuo
7. additionwater (10 ml) and iron powder (2.0 g) added
8. temperatureThe resulting mixture was warmed
9. temperatureto reflux for 2 hours
10. temperaturecooled to room temperature
11. filtrationfiltered through Celite™
12. extractionThe filtrate was extracted with ethyl acetate
13. customthe organic layers separated
14. dry with materialdried (MgSO4)
15. filtrationfiltered
16. customthe solvent removed in vacuo

ORD-Eintrag

ord-17c50da7368f49ea8bb5866a4d9d36eb

Quelldatensatz

uspto-grants-2000_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06127365