反应详情

温度

0 °C

Fuming nitric acid (11 g, 174 mmol) was added to a solution of methyl 2,6-difluorobenzoate (25 g, 145 mmol) in concentrated sulfuric acid (50 mL) at 0° C., and the reaction was stirred for 30 min at 0° C. The reaction mixture was poured over ice-water. The precipitate was filtered off by suction to give the desired product of Step B (25.1 g, 80.6%). 1H NMR (400 MHz, CDCl3) δ ppm 8.13-8.20 (m, 1H), 7.02-7.10 (m, 1H), 3.93 (s, 3H).

1. filtrationThe precipitate was filtered off by suction