反应 #1121774

反应方程式

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

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

pyridine

bromine

→

17a

收率 70.0%

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

收率 70.0%

溶剂

chloroform

chloroform

反应条件

后处理

1. 1
   洗涤the reaction mixture was washed with water
2. 2
   干燥the organic layer dried over Na2SO4
3. 3
   过滤filtered
4. 4
   其他the solvent was removed under reduced pressure
5. 5
   其他The crude product was purified by flash chromatography

实验过程

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).

来源