反应详情

温度

0 °C

A solution of sodium nitrite (1.9 g, 28 mmol) in H2O (10 mL) was added dropwise to a solution of 2-fluoro-4-(trifluoromethoxy)aniline (4.6 g, 24 mmol) in 6 M HCl (24 mL, 144 mmol) at 0° C. After stirring for 15 min at 0° C.; the mixture was added to a suspension of methyl 4-methoxyacetoacetate (3.1 mL, 24 mmol) and sodium acetate (12 g, 144 mmol) in MeOH (50 mL) pre-cooled at 0° C. The formed precipitate was collected by filtration, washed with water and dried under reduced pressure to give the title compound (4.8 g, 58% yield) as yellow crystals: 1H NMR (300 MHz, CDCl3): δ ppm 3.51 (3H, s), 3.94 (3H, s), 4.65 (2H, s), 7.06-7.14 (2H, m), 7.59-7.68 (1H, m), 12.98 (1H, brs).

1. temperaturepre-cooled at 0° C
2. filtrationThe formed precipitate was collected by filtration
3. washwashed with water
4. customdried under reduced pressure