反应详情

Potassium thiocyanate (16.0 g, 165 mmol) and 6-chloropyridine-3-amine (2.6 g, 20.2 mmol) were dissolved in acetic acid (52 mL). To the solution was added dropwise a solution of bromine (3.2 mL, 62.5 mmol) in acetic acid (12 mL) under cooling in a water bath, and the mixture was stirred for 2 hr. The mixture was allowed to warm to room temperature and stirred for 10 hr, and water (30 mL) was added. The reaction mixture was filtered at 85° C., and the insoluble material was suspended in acetic acid (50 mL) and filtered. The obtained filtrate was neutralized with aqueous ammonia solution, and the precipitated solid was collected by filtration and recrystallized from methanol to give the title compound (2.0 g, 54%) as white crystals.

1. temperatureunder cooling in a water bath
2. stirringstirred for 10 hr
3. filtrationThe reaction mixture was filtered at 85° C.
4. filtrationfiltered
5. filtrationthe precipitated solid was collected by filtration
6. customrecrystallized from methanol