反应详情

A mixture of 39.5 g of 5-bromoisatoic acid anhydride, 14.5 g of sarcosine and 150 ml of dimethyl sulphoxide is heated to 100° while stirring. After completion of the gas evolution, the mixture is stirred at 100° for a further 30 minutes and subsequently poured into 900 ml of ice-water. The precipitated crystals are filtered off under suction, washed with water and dried at 50° in vacuo over phosphorus pentoxide. There is obtained 7-bromo-3,4-dihydro-4-methyl-2H-1,4-benzodiazepine-2,5(1H)-dione as light beige crystals. A sample recrystallized from methanol has a melting point of 260°-261°.

1. temperatureis heated to 100°
2. stirringAfter completion of the gas evolution, the mixture is stirred at 100° for a further 30 minutes
3. filtrationThe precipitated crystals are filtered off under suction
4. washwashed with water
5. dry with materialdried at 50° in vacuo over phosphorus pentoxide