Water → 2,6-Dimethylterephthalic acid

Participants

Reaction Conditions

Reaction Steps

2,4,6-Trimethylbenzoic acid (mesitoic acid) (10 g, 61 mmol) was suspended in 150 mL of water, and the mixture cooled to 0° C. Sodium hydroxide pellets (7.31 g, 0.18 mol) were gradually added, followed by addition of potassium permanganate (4×7.2 g, 0.18 mol) at four intervals of 30 minutes. The mixture was stirred at room temperature for 2 hours, then heated on a steam bath for 15-30 minutes. Sulfuric acid (200 mL, 9 mol) was added, then sodium bisulfite was carefully and gradually added at 0° C. The precipitated white solid was filtered and then dissolved in 5 N ammonium hydroxide. The solution was washed with diethyl ether, then gradually treated dropwise with concentrated sulfuric acid to precipitate the product. Filtration, followed by washing with hot water (4×) and petroleum ether (3×), recrystallization (methanol-water), and drying at high vacuum gave 10.5 g (89%) of the product as a white solid, m.p. >300° C. (ref. W. A. Noyes, Amer. Chem. J., 20, 789 (1898)).

Provenance & Evidence