4-Aminobenzoic Acid → 4-(2,5-dihydro-2,5-dioxo-1H-pyrrol-1-yl)benzoic acid

Participants

Reaction Steps

41.1 g (0.3 mol) of p-aminobenzoic acid and 300 ME of acetic acid were put into a 250 Ml flask, dissolved, and then 29.4 g (0.3 mol) of maleic acid anhydride was slowly added at 10° C. to obtain a yellow precipitate. This yellow precipitate was recrystallized using a mixed solution of DMF and ethanol (50:50, w/w). The recrystallized intermediate was treated at 85° C. for 15 minutes using sodium acetate and acetic acid anhydride, cooled to room temperature, and then precipitated using an ice water bath to obtain a precipitate. The obtained precipitate was recrystallized using a mixed solution of ethyl acetate and n-hexane (50:50, w/w) to obtain N-(p-carboxyphenyl) maleimide.

Provenance & Evidence