Ammonia → Quinazolinedione

Participants

Reaction Steps

978 g of isatoic acid anhydride were added in portions with stirring at 150° C. to a mixture of 720 g of urea and 1 liter of dimethylformamide and the mixture was then heated at 180° C. until evolution of ammonia ceased. The mixture was cooled and one liter of water was immediately added thereto followed by the addition of one liter of methanol. The warm mixture was stirred for one hour and was then filtered. The product was rinsed with warm water and with methanol and was then added with stirring to 2-3 volumes of warm dimethylformamide. The mixture was filtered and the product was rinsed with methanol to obtain 747 g of quinazoline-2,4-dione.

Provenance & Evidence