反应详情

温度

80 °C

N-(2,6-dichloropyridin-4-yl)nitramide (205 g crude, 0.617 mol) was added carefully to conc. H2SO4 (800 mL) at room temperature. Then the reaction mixture was stirred at 80° C. for 2 h. TLC (Petroleum ether/ethyl acetate=2:1) showed the reaction was complete. The mixture was cooled to room temperature and poured into crushed ice. The mixture was cooled to 0° C. and neutralized with NaOH and NH4OH. The resulting precipitate was collected by filtration and washed with water. The resulting precipitate was dissolved in ethyl acetate, dried over Na2SO4 and concentrated to give crude 2,6-dichloro-3-nitropyridin-4-amine, which was used for the next step without further purification. 1H NMR (400 MHz, CDCl3) δ: 7.64 (s, 2H), 6.86 (s, 1H).

1. temperatureThe mixture was cooled to room temperature
2. additionpoured
3. custominto crushed ice
4. filtrationThe resulting precipitate was collected by filtration
5. washwashed with water
6. dissolutionThe resulting precipitate was dissolved in ethyl acetate
7. dry with materialdried over Na2SO4
8. concentrationconcentrated