反应详情

3-Amino-6-bromopyrazine-2-carboxamide (1.5 g, 7 mmol) was dissolved in pyridine (15 mL). The solution was then cooled in an ice bath and POCl3 (2 mL) was drop wise added. The resulting mixture was stirred at room temperature for 2.5 h. The solvent was removed and the residue was quenched by the careful addition of ice cooled Na2CO3 (5 mmol). Ethyl acetate was added (45 mL) and the organic layer was separated, washed with brine (5 mL), HCl (0.1 M aqueous solution, 1 mL) and water (5 mmol), dried with K2CO3 and concentrated. The crude matherial was triturated with hexane, and the resulting tan solid was filtered to provide 0.8 g (58% yield) of the title compound: 1H NMR (400 MHz; DMSO-d6): 8.42 (s, 1H); 7.60 (br s, NH); MS (EI) for C5H3BrN4: 199 (MH+).

1. temperatureThe solution was then cooled in an ice bath
2. additionwise added
3. customThe solvent was removed
4. customthe residue was quenched by the careful addition of ice
5. customthe organic layer was separated
6. dry with materialdried with K2CO3
7. concentrationconcentrated
8. customThe crude matherial was triturated with hexane
9. filtrationthe resulting tan solid was filtered