反应详情

2H-[1,2,4]triazin-3,5-dione (50 g, 442 mmol) is placed in the presence of 60 ml of bromine in 800 ml of water at 60° C. for 10 h. The reaction medium is then slowly added to an ammonia solution until pH=5. It is then extracted in ethyl acetate and the organic phases are dried on MgSO4. After filtration and dry concentration, 1a is isolated in the form of a white solid (79.2 g, yield=93%). TLC silica gel 60 F 254 Merck, CH2Cl2:MeOH 90:10, Rf=0.32.

1. extractionIt is then extracted in ethyl acetate
2. customthe organic phases are dried on MgSO4
3. filtrationAfter filtration
4. customdry
5. concentrationconcentration