Reacción #1121774

Ecuación de reacción

2-amino-5-(4-mcthoxyphenyl)pyrazinc

2-Amino-5-(4-methoxyphenyl)pyrazine

pyridine

bromine

→

17a

Rendimiento 70.0%

2-Amino-3-bromo-5-(4-methoxyphenyl)pyrazine

Rendimiento 70.0%

Disolventes

chloroform

chloroform

Condiciones de reacción

Tratamiento posterior

1. 1
   Lavadothe reaction mixture was washed with water
2. 2
   Secadothe organic layer dried over Na2SO4
3. 3
   Filtraciónfiltered
4. 4
   Otrothe solvent was removed under reduced pressure
5. 5
   OtroThe crude product was purified by flash chromatography

Procedimiento

To a solution of 2-amino-5-(4-mcthoxyphenyl)pyrazinc 16a (0.35 g, 1.7 mmol) and pyridine (0.20 mL, 2.6 mmol) in chloroform (20 mL), bromine (Br2) (0.13 mL, 2.6 mmol) was added dropwise in chloroform (3 mL) at −10° C. After 6 h stirring at room temperature, the reaction mixture was washed with water, the organic layer dried over Na2SO4, filtered and the solvent was removed under reduced pressure. The crude product was purified by flash chromatography using dichloromethane-EtOAc (90:10 v/v) as eluent, to obtain 0.33 g of 17a as an brown solid (mp 166-170° C., 70% yield). 1H-NMR (CDCl3): 3.83 (s, 3H), 5.04 (br s, 2H), 6.92-6.96 (m, 2H), 7.76-7.80 (m, 2H), 8.31 (s, 1H). GC-MS (EI): m/z 279,281 (M1, 100).

Fuente