Acetic Anhydride → 4-Cyanobenzoic acid

Participants

Reaction Steps

Acetic acid (30 ml), acetic anhydride (70 ml), and p-cyanobenzamide (5 g) were mixed with stirring under cooling with ice, to thereby obtain a mixture. The mixture was allowed to react while dinitrogen trioxide gas was introduced thereto at 190 N ml/hour for six hours. The residual solvent was removed through distillation in vacuum, and water was added to the residue, to thereby form crystals. The precipitated crystals were collected through filtration, washed with water, and dried, to thereby obtain 4.73 g of p-cyanobenzoic acid (yield 94%, based on p-cyanobenzamide). High performance liquid chromatographic analysis revealed that the p-cyanobenzoic acid obtained had a purity of 99% or more.

Provenance & Evidence