Reacción #465959

Ecuación de reacción

methyl 4-amino-6-bromo-3-chloropyridine-2-carboxylate

NaOH

→

4-amino-6-bromo-3-chloropyridine-2-carboxylic acid

Rendimiento 34.8%

Disolventes

methanol

Condiciones de reacción

Tratamiento posterior

1. 1
   Otroevaporated to dryness in vacuo
2. 2
   workup.DISSOLUTIONThe residue was dissolved in water
3. 3
   OtroAfter separation of the phases
4. 4
   OtroThe aqueous layer was evaporated to dryness
5. 5
   workup.DISSOLUTIONthe residue was dissolved in 50 mL of methanol
6. 6
   Filtraciónfiltered
7. 7
   OtroThe filtrate was evaporated under reduced pressure
8. 8
   Otrothe residue was triturated with 5 percent diethyl ether in petroleum ether

Procedimiento

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.

Fuente