反应详情

A solution of bromine (0.26 ml) in chloroform (40 ml) was added dropwise to a stirred solution of 2-amino-3-methylpyrazine (0.453 g) and pyridine (0.4 ml) in chloroform (100 ml) with shielding from sunlight, over a period of 1 hour. The reaction mixture was stirred for a further 30 minutes and then water (25 ml) was added. The organic layer was separated, dried (MgSO4) and evaporated to afford a brown oil. The oil was purified by chromatography on silica gel, eluting with dichloromethane, to give 2-amino-5-bromo-3-methylpyrazine as a white solid (0.312 g, 28%), m.p. 51°-52° C.; mass spectrum (+ve CI): 188 (M+H)+.

1. customThe organic layer was separated
2. dry with materialdried (MgSO4)
3. customevaporated
4. customto afford a brown oil
5. customThe oil was purified by chromatography on silica gel
6. washeluting with dichloromethane