1. cool sulfuric acid (53.3 mL, 760 mmol) in an ice-water bath and slowly add nitric acid (25.6 mL, 610 mmol), keeping the temperature below 10°C. 2. add N-(2,6-difluorophenyl)acetamide (13.0 g, 76.0 mmol) to the mixed acid solution.
2. N-(2,6-difluorophenyl)acetamide (13.0 g, 76.0 mmol) was added to the above mixed acid solution in batches, ensuring that the reaction temperature was maintained at room temperature.
3. The reaction mixture was stirred at room temperature for 18 hours to carry out the nitration reaction.
4. Upon completion of the reaction, the mixture was slowly poured into ice water to precipitate a yellow solid.
5. The precipitate was collected by filtration and the solid residue was washed well with cold water.
6. The product was dried over air to give 2,6-difluoro-3-nitro-acetanilide (11.2 g, 51.8 mmol, 68% yield) as a yellow solid. 7. The product was analyzed by LCMS (1:1).
7. The product was characterized by LCMS (ESI, cationic mode): calculated C8H6F2N2O3 [M+H]+ 216.0, measured 217.2. 8. 1H NMR (ESI, cationic mode) was performed on the product.
8. 1H NMR (300 MHz, DMSO-d6) δ ppm: 10.04 (br s, 1H, NH), 8.02-8.28 (m, 1H, ArH), 7.44 (td, J = 9.1, 1.8 Hz, 1H, ArH), 2.11 (s, 3H, CH3).
