Nitric Acid → 5-Fluoro-4-methyl-2-nitrophenol

3-fluoro-4-methylphenol (3.66 g, 29.0 mmol) was dissolved in dichloroethane (32 mL) and tetrabutylammonium bromide (0.935 g, 2.90 mmol) was added. Nitric acid 70% (3.7 mL, 58 mmol) was diluted with water (33 mL) to make a 7% nitric acid solution. This solution was added to the reaction mixture which was then stirred at room temperature for 4 h at which time the reaction was judged complete by TLC. The reaction was poured into water and extracted with dichloromethane (3×). The combined organic layers were dried over magnesium sulfate, filtered and concentrated in vacuo. The resulting residue was absorbed onto silica gel and purified by chromatography on SiO2 to give 5-fluoro-4-methyl-2-nitrophenol as a yellow solid (2.83 g, 57%). 1H NMR (400 MHz, DMSO-d6) δ ppm 11.10 (s, 1 H), 7.89 (d, J=8.1 Hz, 1 H), 6.85 (d, J=11.0 Hz, 1 H), 2.13 (s, 3 H).

1. additionThis solution was added to the reaction mixture which
2. extractionextracted with dichloromethane (3×)
3. dry with materialThe combined organic layers were dried over magnesium sulfate
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customThe resulting residue was absorbed onto silica gel
7. custompurified by chromatography on SiO2

ORD record

ord-827747572a154d5cbc8cacc217178bc0

Source dataset

uspto-grants-2011_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07981903B2