Potassium Nitrate → HCID 22097122, compound

Participants

Reaction Conditions

Reaction Steps

57.5 g (0.19 mol) of 7-acetamido-1-(ethoxycarbonylmethyl)-2,3(1H,4H)-quinoxalinedione were dissolved in 575 ml of concentrated sulfuric acid. The solution was cooled to 0° C., and 19.0 g (0.19 mol) of potassium nitrate were added a little at a time. The cooling was then removed and the mixture was stirred until the reaction was complete and was then poured into 2 l of ice-water and heated on a water bath for 2 h. The pH was then adjusted with aqueous ammonia solution to about 4-5, and the precipitate was filtered off with suction. The filtrate was concentrated under reduced pressure, and the residue was purified by chromatography on silica gel (mobile phase: methanol/tetrahydrofuran/water==5:4:1+2.5% glacial acetic acid). The resulting product was combined with the first precipitate to yield 36.9 g (70%) of product.

Provenance & Evidence