反应详情

2-Acetylamino-isonicotinic acid (3.10 g, 17.2 mmol) was stirred in 35 mL MeOH at 0° C. HCl (g) was bubbled through the solution for 10 minutes and then the reaction was heated to reflux. After 16 hours the reaction was concentrated in vacuo. The residue was diluted with water and the pH was adjusted to 7 with Na2CO3 (s). A white precipitate formed which was filtered to afford a portion of pure desired product. The aqueous phase was extracted three times with 95:5 dichloromethane (DCM)/nBuOH. The organic phases were dried over Na2SO4, filtered and concentrated to afford more of the pure product as a white solid. 1H NMR (CDCl3) δ 8.19 (d, 1H, J=5.3 Hz), 7.17 (dd, 1H, J=1.4, 5.3 Hz), 7.07 (d, 1H, J=1.3 Hz), 4.64 (bs, 2H), 3.92 (s, 3H). MS [M+H]+=153.0.

1. customHCl (g) was bubbled through the solution for 10 minutes
2. temperaturethe reaction was heated to reflux
3. concentrationAfter 16 hours the reaction was concentrated in vacuo
4. additionThe residue was diluted with water
5. customA white precipitate formed which
6. filtrationwas filtered