反应详情

温度

175 °C

To a flask containing methyl 8-bromo-4-butyl-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate (0.33 g) was added NMP (7 mL), followed by copper cyanide (0.18 g). The mixture was then heated to 175° C. and stirred overnight. The resulting mixture was cooled to room temperature and poured into 1 N hydrochloric acid. The acidic aqueous layer was extracted with ethyl acetate, washed with 1 N hydrochloric acid (15 mL), saturated sodium bicarbonate (15 mL), and brine, dried (magnesium sulfate), filtered, and concentrated under reduced pressure. Purification by flash column chromatography (silica, 1:9 ethyl acetate/hexanes) provided 184 mg of the title compound: 1H NMR (300 MHz, CDCl3) δ 7.55, 7.43, 4.41, 3.89, 3.39, 3.31, 1.58, 1.40, 0.97.

1. temperatureThe resulting mixture was cooled to room temperature
2. extractionThe acidic aqueous layer was extracted with ethyl acetate
3. washwashed with 1 N hydrochloric acid (15 mL), saturated sodium bicarbonate (15 mL), and brine
4. dry with materialdried (magnesium sulfate)
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customPurification by flash column chromatography (silica, 1:9 ethyl acetate/hexanes)