反应详情

温度

75 °C

In a 1 l round-bottomed flask was added ethyl 2-(5-bromo-3-nitropyridin-2-yloxy)acetate (18.33 g, 60.1 mmol), phenylboronic acid (10.99 g, 90 mmol), triphenylphosphine (4.73 g, 18.02 mmol) and cesium fluoride (45.6 g, 300 mmol) in 1,2-dimethoxyethane (300 ml) to give a yellow solution. The reaction mixture was degassed by bubbling nitrogen for 30 minutes. Palladium(II)acetate (2.023 g, 9.01 mmol) was added and the mixture was heated to 75° C. under a nitrogen atmosphere overnight. The reaction mixture was allowed to cool to room temperature and concentrated to dryness under reduced pressure to give a brown solid. This was re-dissolved in dichloromethane, filtered and concentrated to dryness under reduced pressure to give a brown solid The crude residue was purified via Biotage chromatography (gradient 5% to 60% ethyl acetate in n-hexanes) to give the title compound (6.9 g, 38%). 1H NMR (500 MHz, CDCl3) δ 8.58 (1H, s), 8.56 (1H, s), 7.59-7.52 (2H, m), 7.48-7.46 (2H, m), 7.45-7.43 (1H, m), 5.13 (2H, s), 4.30-4.26 (2H, q), 1.33-1.30 (3H, t).

1. customto give a yellow solution
2. customThe reaction mixture was degassed
3. customby bubbling nitrogen for 30 minutes
4. temperatureto cool to room temperature
5. concentrationconcentrated to dryness under reduced pressure
6. customto give a brown solid
7. filtrationfiltered
8. concentrationconcentrated to dryness under reduced pressure
9. customto give a brown solid The crude residue
10. customwas purified via Biotage chromatography (gradient 5% to 60% ethyl acetate in n-hexanes)