反应详情

2,6-Dimethyl-1,4-benzenedicarboxylic acid (from Preparation 7) (5.0 g, 26mmol) was suspended in methanol (40 mL), concentrated sulfuric acid (5 mL) was added, and the mixture was heated at reflux for 2 hours. The solution was cooled, and water was added to precipitate the product. Filtration, followed by washing with water (3×) and petroleum ether (3×), and drying at high vacuum gave 2.05 g of the product as a white powder, m.p. 191°-192° C. (ref. W. A. Noyes, cited above).

1. temperaturethe mixture was heated
2. temperatureat reflux for 2 hours
3. temperatureThe solution was cooled
4. customto precipitate the product
5. filtrationFiltration
6. washby washing with water (3×) and petroleum ether (3×)
7. customdrying at high vacuum