2(1H)-Quinoxalinone → 6-Bromo-1,2-dihydroquinoxalin-2-one

Participants

Reaction Conditions

Reaction Steps

The quinoxalin-2(1H)-one (14.6 g, 0.1 mol, Aldrich, cat. no. 260517) and silver sulphate (15.6 g, 0.05 mol) were dissolved in conc. Sulfuric acid (100 ml) at 20° C. Bromine (5.2 ml, 0.1 mol) was added and the reaction mixture was stirred vigorously for 24 hours. The reaction mass was then diluted with carbon tetrachloride (100 mL), and this was heated at 50° C. The reaction mass was then filtered and the filtrate was poured into ice cold water and stirred for 30 minutes to obtain a precipitate. The precipitate was filtered and the solid material was dried in vacuo to afford the title product (9.0 g, 40%).

Provenance & Evidence