Nitric Acid → 1-Bromo-2,4-difluoro-5-nitrobenzene

Temperature

0 °C

To a suspension of 1-bromo-2,4-difluorobenzene (11.7 mL, 104 mmol) in 96 mL concentrated H2SO4 at 0° C. was added concentrated HNO3 (85 mL) dropwise maintaining the temperature below 20° C. The resulting mixture was stirred for 10 minutes at 0° C., then poured into a mixture of ether and ice water with vigorous stirring. The aqueous phase was separated and extracted with ether. The combined organic phases were washed with aqueous NaHCO3 and brine, dried and concentrated. The residue was purified using silica gel column chromatography with 15% acetone in hexanes to provide 1-bromo-2,4-difluoro-5-nitrobenzene (23 g, 96.6 mmol, 93.3% yield) as yellow oil.

1. temperaturedropwise maintaining the temperature below 20° C
2. customThe aqueous phase was separated
3. extractionextracted with ether
4. washThe combined organic phases were washed with aqueous NaHCO3 and brine
5. customdried
6. concentrationconcentrated
7. customThe residue was purified

ORD record

ord-da0457ed844347f2b0e2bb4ce05e19ad

Source dataset

uspto-grants-2014_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08754226B2