反应详情

温度

90 °C

To a solution of 3-amino-6-bromopyrazine-2-carboxamide (200 mg, 0.92 mmol) in triethoxymethane (10 mL) was added Ac2O (2 mL). The mixture was stirred at 130° C. for 1 h and 90° C. for 3 h. After being cooled to RT and extracted with EtOAc, the combined organic phases were basified to pH=8 with a.q. NaHCO3, washed with brine, dried over Na2SO4, filtered and evaporated. The crude product was purified by prep-TLC (DCM:MeOH=50:1) to give the product of 6-bromopteridin-4(3H)-one (100 mg, yield: 48%). 1H-NMR (DMSO-d6, 400 MHz) δ 8.59 (s, 1H), 7.89 (s, 1H). MS (M+H)+: 227/229.

1. temperatureAfter being cooled to RT
2. extractionextracted with EtOAc
3. washNaHCO3, washed with brine
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. customevaporated
7. customThe crude product was purified by prep-TLC (DCM:MeOH=50:1)