反应详情

温度

80 °C

The title compound of Step B (2.0 g, 8 mmol) was dissolved in 10 mL of acetic acid and treated with bromine (0.4 mL, 8 mmol). The mixture was heated at 80° C. until the orange color was discharged (1 h). The mixture was evaporated under reduced pressure, diluted with 50 mL of ether and washed twice with 50 mL of sodium bicarbonate and then 50 mL of brine. The organic layer was dried over magnesium sulfate and concentrated under reduced pressure to yield 2.54 g of the title compound of Step C as a tan solid which was used immediately in the next step without further purification. 1H NMR (CDCl3): δ2.44 (s, 3H), 4.54 (s, 2H), 7.74 (d, 2H), 8.56 (d, 2H), 8.62 (s, 1H).

1. custom(1 h)
2. customThe mixture was evaporated under reduced pressure
3. additiondiluted with 50 mL of ether
4. washwashed twice with 50 mL of sodium bicarbonate
5. dry with materialThe organic layer was dried over magnesium sulfate
6. concentrationconcentrated under reduced pressure