Ammonia → HCID 19027047, compound

Participants

Reaction Steps

A solution of 0.5 g (1.36 mmol) 4-bromo-1-ethoxalylamino-2-nitronaphthalene in 30 ml tetrahydrofuran was added 10 ml dimethylformamide and 0.7 ml 25% aqueous ammonia. The mixture was hydrogenated at atm. pressure by using 50 mg 5% Pd-C as a catalyst. The precipitated product was filtered off and washed with tetrahydrofuran. The filter cake was washed several times with 5% aqueous potassium hydroxide. Acidification of the filtrate with 4N hydrochloric acid and recrystallization (dimethylformamide-water) of the precipitated product gave 0.2 g (65%) 4-hydroxy-benzo[f]quinoxaline-2,3(1H,4H)-dione. M.p. 270° C. decomp. 1H-NMR (DMSO-d6 : 12.1 (1H, broad s), 8.6 (1H, m), 7.7 (5H, m). MS (m/e): 228 (M+, 90%).

Provenance & Evidence