2(1H)-Quinoxalinone → 7-bromo-1H-quinoxalin-2-one

Participants

Reaction Steps

Bromine (7.36 mL, 147 mmol, 1.05 eq) is added at room temperature to a stirred suspension of 1H-quinoxalin-2-one (20 g, 137 mmol, 1.0 eq) in acetic acid (400 mL). After 48 hours stirring at room temperature, the reaction mixture is poured into ice (500 mL) and the resulting precipitate is collected by filtration, washed with water and ethyl acetate to afford 7-bromo-1H-quinoxalin-2-one as a yellow solid (29.4 g, 73% yield).

Provenance & Evidence