C[O:2][C:3](=[O:12])[C:4]1[CH:9]=[C:8]([F:10])[C:7]([CH3:11])=[N:6][CH:5]=1.CO.[OH-].[Na+]>O>[F:10][C:8]1[C:7]([CH3:11])=[N:6][CH:5]=[C:4]([CH:9]=1)[C:3]([OH:12])=[O:2]To a suspension of 5-fluoro-6-methyl-nicotinic acid methyl ester (0.21 g, 1.24 mmol) in a 1:1 mixture of MeOH:water (20 mL) is added sodium hydroxide as a 10% aqueous solution (1.0 mL, 2.5 mmol). The mixture is heated to 50° C. for 1 h then cooled to room temperature and concentrated under reduced pressure to remove volatile organics. The pH of the resulting solution is adjusted to slightly acidic (approximately pH 5) by the addition of a 2N solution of HCl. The mixture is extracted with EtOAc and the combined organic phase is dried over anhydrous sodium sulfate and concentrated to provide 0.170 g of 5-fluoro-6-methyl-nicotinic acid as a solid.
Wird geladen…
