Acetic Anhydride → 6-Bromopteridin-4-ol

Participants

Reaction Conditions

Reaction Steps

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.

Provenance & Evidence