Acetic Acid → 2-Fluoro-3-nitrobenzoic acid

Temperature

95 °C

Concentrated sulfuric acid (195 ml) was added carefully with stirring to a solution of 2-fluoro-3-nitrotoluene (100 g, 645 mmol) in acetic acid (1000 ml). The mixture was warmed up to 95° C. and the solution of chromium trioxide (226 g, 2.25 mol) in water (200 ml) was added dropwise with stirring over 2 h. After addition the mixture was heated with stirring for another 3 h, allowed to cool down to room temperature and poured into water (3 L). The mixture was extracted with ethyl acetate (3×1 L), the combined organic layers were dried over Na2SO4 and concentrated under reduced pressure to afford a light green solid, which was washed with dichloromethane (3×300 ml) and dried under vacuum to afford the title compound was obtained as a light yellow solid (75 g, 62.8%). 1H NMR (300 MHz, DMSO) δ ppm 8.27 (m, 1H), 8.15 (m, 1H), 7.48 (m, 1H).

1. additionAfter addition the mixture
2. temperaturewas heated
3. stirringwith stirring for another 3 h
4. temperatureto cool down to room temperature
5. extractionThe mixture was extracted with ethyl acetate (3×1 L)
6. dry with materialthe combined organic layers were dried over Na2SO4
7. concentrationconcentrated under reduced pressure
8. customto afford a light green solid, which
9. washwas washed with dichloromethane (3×300 ml)
10. customdried under vacuum

ORD record

ord-d6fe03486dcd4bb6a2053aeab32f3c55

Source dataset

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08642759B2