反应详情

To methyl 4-amino-6-bromo-3-chloropyridine-2-carboxylate (200mg; 0.8 mmol) in 10 mL of methanol was added excess 2N NaOH (10 mL). The mixture was stirred for 1 hr at ambient temperature and then evaporated to dryness in vacuo. The residue was dissolved in water and diethyl ether. After separation of the phases, the aqueous layer was acidified with 1N HCl to a pH=2. The aqueous layer was evaporated to dryness and the residue was dissolved in 50 mL of methanol and filtered. The filtrate was evaporated under reduced pressure and the residue was triturated with 5 percent diethyl ether in petroleum ether to give 70 mg of 4-amino-6-bromo-3-chloropyridine-2-carboxylic acid, mp 182-183° C.

1. customevaporated to dryness in vacuo
2. dissolutionThe residue was dissolved in water
3. customAfter separation of the phases
4. customThe aqueous layer was evaporated to dryness
5. dissolutionthe residue was dissolved in 50 mL of methanol
6. filtrationfiltered
7. customThe filtrate was evaporated under reduced pressure
8. customthe residue was triturated with 5 percent diethyl ether in petroleum ether