Nitric Acid → 2,5-Dibromo-4-methylbenzoic acid

Participants

Reaction Steps

To a mixed solution of nitric acid (45 ml, 70-71%) and water (55 ml) was added portionwise 2,5-dibromo-p-xylene 802 (13.2 g, 50 mmol). The resulting mixture was heated to reflux and continued to reflux for 6 days. The mixture was cooled to room temperature and the white solid was collected by filtration. The solid was placed into a mixture of ethyl acetate (100 ml) and water (100 ml), to which was added sodium carbonate portion wise (ca 10-12 g) over a 2 hour period until all the solid dissolved. The organic layer was separated and the aqueous layer was made strongly acidic by the addition of concentrated HCl to pH 2-3. A white solid was collected by filtration and dried in vacuum to give 2,5-dibromo-4-methylbenzoic acid: 9.6 g (65%).

Provenance & Evidence