Nitric Acid → Methyl 4-hydroxy-5-nitro-2-(trifluoromethyl)benzoate

Temperature

65 °C

Methyl 4-hydroxy-2-(trifluoromethyl)benzoate (32.0 g) was dissolved in acetic acid (180 ml), and thereto was added conc. sulfuric acid (0.45 ml), and the mixture was heated to 65° C. Then, thereto was slowly added a 70% solution of conc. nitric acid (12.4 g) in acetic acid (60 ml) dropwise, and the mixture was stirred at 65° C. for one hour. The reaction mixture was cooled to room temperature, and poured into ice-water (500 ml), and the mixture was extracted twice with toluene (800 ml). The organic layer was washed with water and a saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered and concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (hexane/ethyl acetate) to give the title compound (15.0 g).

1. temperatureThe reaction mixture was cooled to room temperature
2. extractionthe mixture was extracted twice with toluene (800 ml)
3. washThe organic layer was washed with water
4. dry with materiala saturated aqueous sodium chloride solution, dried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customThe obtained residue was purified by silica gel column chromatography (hexane/ethyl acetate)

ORD record

ord-b221ee231e524bc594311615467cdd00

Source dataset

uspto-grants-2013_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08389511B2