Hydrochloric Acid → 5-Ethoxycarbonyl-2-isobutyrylamino-4,6-dimethylbenzoic acid

Participants

Reaction Steps

To an ice-cooled mixture consisting of 500 mg of 2-amino-5-ethoxycarbonyl-4,6-dimethylbenzoic acid, 15 ml of benzene, and 0.3 ml of pyridine was added dropwise with stirring a solution of 323 mg of isobutyryl chloride in 2 ml of benzene. After completion of the addition, the reaction mixture was further stirred for 5 hours at room temperature, and then heated to reflux for one hour. After cooling, the mixture was shaken with dilute hydrochloric acid and the layers were separated. The slightly acidic aqueous layer was extracted with ethyl acetate, and the combined organic extracts were washed with water, dried over anhydrous sodium sulfate, and evaporated. The resulting residue was recrystallized from ethyl ether/n-hexane to yield 523 mg of 5-ethoxycarbonyl-2-isobutyrylamino-4,6-dimethylbenzoic acid.

Provenance & Evidence