Carbon Dioxide → 2,6-Dichloro-4-methoxynicotinic Acid

To a solution of diisopropylamine (1.83 mL) in tetrahydrofuran (40 mL) was added n-butyllithium (2.64 mol/L n-hexane solution, 4.52 mL) at −78° C., and the mixture was stirred at the same temperature for 5 minutes. To the reaction mixture was added a solution of 2,6-dichloro-4-methoxypyridine (1.93 g) in tetrahydrofuran (10 mL) in a dropwise manner, and the mixture was stirred at the same temperature for 30 minutes. To the reaction mixture was added dry ice (5 g), and the mixture was stirred at the same temperature for 30 minutes. To the reaction mixture were added a saturated aqueous ammonium chloride solution and 2 mol/L hydrochloric acid, and the resulting mixture was extracted with ethyl acetate. The extract was washed with brine, and dried over anhydrous magnesium sulfate. The solvent was removed under reduced pressure, and the residue was purified by column chromatography on silica gel (eluent: ethyl acetate) to give the title compound (1.2 g).

1. stirringthe mixture was stirred at the same temperature for 30 minutes
2. stirringthe mixture was stirred at the same temperature for 30 minutes
3. extractionthe resulting mixture was extracted with ethyl acetate
4. washThe extract was washed with brine
5. dry with materialdried over anhydrous magnesium sulfate
6. customThe solvent was removed under reduced pressure
7. customthe residue was purified by column chromatography on silica gel (eluent: ethyl acetate)

ORD-Eintrag

ord-689eef47678e4e90a528f7eafd53bfb9

Quelldatensatz

uspto-grants-2012_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08217069B2