Ammonia → HCID 118599044, compound

Temperature

45 °C

In a round bottom flask containing ethyl 5-bromo-3-chloro-6-oxo-1H-pyridine-2-carboxylate (4, 75.0 g, 267.38 mmol) was added liquid ammonia (150.0 mL, 267.38 mmol) in ethanol (100 mL) at 0° C. The reaction mixture was stirred at 45° C. for 2 h. At this time the mixture was concentrated to remove the ethanolic ammonia. The crude solids were washed with diethyl ether (500 mL) and dissolved in refluxing methanol (1 L) and filtered hot. The filtrate was concentrated under reduced pressure until ⅓ of solvent volume remained. Diethyl ether was added until all solids precipitated. The solid was filtered and dried under vacuum to afford 5-bromo-3-chloro-6-oxo-1H-pyridine-2-carboxamide (5) as a light brown solid. Yield: 45 g, 69%; MS (ESI) m/z 248.9 [M−1]−; 1H NMR (400 MHz, DMSO-d6) δ 7.92-7.82 (m, 1H), 7.61-7.59 (m, 1H), 7.36 (s, 1H).

1. concentrationAt this time the mixture was concentrated
2. customto remove the ethanolic ammonia
3. washThe crude solids were washed with diethyl ether (500 mL)
4. dissolutiondissolved
5. temperaturein refluxing methanol (1 L)
6. filtrationfiltered hot
7. concentrationThe filtrate was concentrated under reduced pressure until ⅓ of solvent volume
8. additionDiethyl ether was added until all solids
9. customprecipitated
10. filtrationThe solid was filtered
11. customdried under vacuum

ORD record

ord-120d907dd0324dd88f964999c3af4dae

Source dataset

uspto-grants-2016_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09382248B2