Acetic Anhydride → 5-(4-acetamidophenyl)-2(1H)-pyrazinone

Participants

Reaction Steps

5-(4-Aminophenyl)-2(1H)-pyrazinone hydrobromide (2.5 g) in water (20 ml) was treated with acetic anhydride (1.2 g) and anhydrous sodium acetate (1.4 g). The mixture was stirred at room temperature for 1 hour, and the crude product (1.58 g; m.p. 268°-275° C.) was filtered off. This material was thoroughly washed with water and recrystallised from glacial acetic acid to give 5-(4-acetamidophenyl)-2(1H)-pyrazinone (0.84 g; m.p. 287°-8° C.).

Provenance & Evidence