Реакция #1121774

Уравнение реакции

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

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

pyridine

bromine

→

17a

Выход 70.0%

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

Выход 70.0%

Растворители

chloroform

chloroform

Условия реакции

Обработка

1. 1
   Промывкаthe reaction mixture was washed with water
2. 2
   Сушкаthe organic layer dried over Na2SO4
3. 3
   Фильтрацияfiltered
4. 4
   Другоеthe solvent was removed under reduced pressure
5. 5
   ДругоеThe crude product was purified by flash chromatography

Методика

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).

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