反应详情

Dissolve ethyl 5-fluoropyridine-2-carboxylate (4.60 g, 27.2 mmol) in THF (34 mL) and methanol (34 mL). Add 1.0 N NaOH (32.6, 32.6 mmol) and stir at room temperature for 1.3 hours. Concentrate the reaction mixture. Then add 1.0 N HCl (32.6 mL), stir and concentrate. Take the solid up in 20% methanol, 3% AcOH and 77% dichloromethane and filter through a silica plus. Wash the plug with the solvent listed above until all of the product elutes off to give the title compound (3.8 g, 100%): MS ES+ 142.03 (M+H)+, HRMS calcd for C6H5NO2F 142.0304 (M+H)+, found 142.0306, time 0.46 min, 0.51; HPLC [YMC-Pack Pro C-18 (150×4.6 mm, S-5 microm), 0.1% TFA/acetonitrile in 0.1% TFA/water at 1.0 mL/min, 5-95% over 19 min], tR=6.3 min, 100% purity.

1. concentrationConcentrate the reaction mixture
2. additionThen add 1.0 N HCl (32.6 mL)
3. stirringstir
4. concentrationconcentrate
5. filtrationfilter through a silica plus
6. washWash the plug with the solvent