反应详情

3-amino-2-chloro-4-methylpyridine (2 g) was added to a mixed solvent of a 48% aqueous hydrogen bromide solution (17 mL) and water (12 mL). Sodium nitrite (2.5 g) was added to the solution at 0° C. Further, bromine (22 mL) was added. The reaction mixture was warmed to room temperature and stirred for 12 hours. The reaction mixture was partitioned by adding a 5 N aqueous sodium hydroxide solution and ethyl acetate. The organic layer was washed with brine and then dried over anhydrous magnesium sulfate. The desiccant was removed by filtration. The filtrate was concentrated under reduced pressure to give the title compound (1.7 g).

1. customThe reaction mixture was partitioned
2. additionby adding a 5 N aqueous sodium hydroxide solution and ethyl acetate
3. washThe organic layer was washed with brine
4. dry with materialdried over anhydrous magnesium sulfate
5. customThe desiccant was removed by filtration
6. concentrationThe filtrate was concentrated under reduced pressure