Ammonia → 2,6-Dimethyl-3-nitropyridin-4(1H)-one

To a cooled (0° C.) solution of sulfuric acid (4.0 mL, 16.24 mmol) was added fuming nitric acid (4.0 mL, 16.24 mmol) via pipette over 5 min. The reaction was maintained at 0° C. for 30 min, at which time 2,6-dimethylpyridin-4(1H)-one (2.0 g, 16.24 mmol) was added as a solid over 5 min. The mixture was allowed to warm to ambient temperature and was stirred for 3 days. The reaction mixture was then heated at 100° C. for 2 h, at which time it was allowed to cool to ambient temperature. The red fumes were blown into a base trap with nitrogen and the reaction mixture was poured over ˜33 g of ice. The mixture was cooled in an ice bath and was stirred (some precipitate formed). The reaction was treated with 8 M NaOH and the pH was further adjusted to ˜5.3 with formic acid and ammonia. The mixture was stirred for 5 min and cooled in a freezer for 15 min. The solids were filtered, washed with water, air dried for 5 min, and further dried in a vacuum oven at 37° C. overnight to give 2,6-dimethyl-3-nitropyridin-4(1H)-one (440 mg, 2.56 mmol, 15.79% yield). 1H NMR (400 MHz, DMSO-d6) δ 2.22 (s, 3H) 2.28 (s, 3H) 6.18 (s, 1H) 11.84 (br. s., 1H). MS(ES) [M+H]+ 168.9.

1. additionwas added as a solid over 5 min
2. temperatureThe reaction mixture was then heated at 100° C. for 2 h, at which time it
3. temperatureto cool to ambient temperature
4. customThe red fumes were blown into a base trap with nitrogen
5. temperatureThe mixture was cooled in an ice bath
6. stirringwas stirred (some precipitate
7. customformed)
8. stirringThe mixture was stirred for 5 min
9. temperaturecooled in a freezer for 15 min
10. filtrationThe solids were filtered
11. washwashed with water, air
12. customdried for 5 min
13. customfurther dried in a vacuum oven at 37° C. overnight

ORD record

ord-4146266f832142f8b9f0449670569e25

Source dataset

uspto-grants-2016_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09382234B2