Carbon Dioxide → 6-Oxo-5-(trifluoromethyl)-1,6-dihydropyridine-3-carboxylic acid

Temperature

-78 °C

To a solution of 5-bromo-3-(trifluoromethyl)pyridin-2-ol (0.960 g, 3.97 mmol, Aldrich) in THF (20 mL) at −78° C. under N2 was slowly added n-butyllithium solution, 1.6 M in hexane (5.45 mL, 8.73 mmol). After addition, the mixture was stirred at −78° C. for 30 min. Then, dry ice was added and the mixture was stirred at −78° C. for 30 min and at rt for 30 min. Water (20 mL) was then added slowly, and the mixture was stirred at rt for 15 min. The aqueous phase was collected and acidified (pH=5-6) using concentrated HCl. The mixture was extracted with EtOAc (3×15 mL). The combined organic layers were dried (MgSO4), concentrated, and dried in vacuo to give the title compound as a yellow solid. MS (ESI, positive ion) m/z: 208 (M+H).

1. customat −78° C.
2. additionAfter addition
3. stirringthe mixture was stirred at −78° C. for 30 min and at rt for 30 min
4. stirringthe mixture was stirred at rt for 15 min
5. customThe aqueous phase was collected
6. extractionThe mixture was extracted with EtOAc (3×15 mL)
7. dry with materialThe combined organic layers were dried (MgSO4)
8. concentrationconcentrated
9. customdried in vacuo

ORD record

ord-f442d49442e84a37ad66273b713634db

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08710043B2