反应详情

温度

200 °C

A mixture of 2-amino-5-bromo-pyridine-3-carboxylic acid (1 g), 2-amino-6-fluoro-phenol (0.586 g) and polyphosphoric acid (10 g) was stirred at 200° C. for 5 hours. The resulting mixture was cooled to room temperature, diluted with water (4 ml) and basified to pH 12 with aqueous NaOH 10N, then 2N. The precipitate was filtered, washed with water, diethyl ether, and dried. The compound was stirred in THF during 2 days, the insoluble was filtered, the filtrate was concentrated to dryness and dried under vacuum to give 5-bromo-3-(7-fluoro-1,3-benzoxazol-2-yl)pyridin-2-amine (0.475 g). NMR Spectrum: (DMSOd6) 7.37-7.48 (m, 2H), 7.69 (dd, 1H), 7.83 (bs, 2H), 8.34 (d, 1H), 8.38 (d, 1H); Mass spectrum: M+H+ 307-309

1. temperatureThe resulting mixture was cooled to room temperature
2. filtrationThe precipitate was filtered
3. washwashed with water, diethyl ether
4. customdried
5. stirringThe compound was stirred in THF during 2 days
6. filtrationthe insoluble was filtered
7. concentrationthe filtrate was concentrated to dryness
8. customdried under vacuum