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 min and then the reaction was heated to reflux. After 16 h 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 time with 95:5 DCM/nBuOH. The organic phases were dried over Na2SO4, filtered and concentrated to afford more of the pure desired product as a white solid. 1H NMR (CDCl3) δ8.19 (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 min
2. temperaturethe reaction was heated to reflux
3. concentrationAfter 16 h the reaction was concentrated in vacuo
4. additionThe residue was diluted with water
5. customA white precipitate formed which
6. filtrationwas filtered