Acetic Anhydride → 3,8-Dimethyl-3,7-dihydro-1H-purine-2,6-dione

Participants

Reaction Steps

A solution of 5,6-diamino-1-methyluracil (2.5 g) in acetic anhydride (25 ml) was heated at reflux for 2 hours and then the acetic anhydride was evaporated under reduced pressure. The residue was dissolved in 10% aqueous sodium hydroxide solution (50 ml) and heated at reflux for 2 hours. After cooling to room temperature, the mixture was acidified to pH 4 by addition of concentrated hydrochloric acid. The precipitate was filtered, washed with water (15 ml), rinsed with acetone (15 ml) and dried under vacuum to provide 3,8-dimethylxanthine (1.8 g).

Provenance & Evidence