反应详情

24 g (132.5 mmol) of 5-fluoroisatoic acid anhydride are dissolved in 140 ml of dimethyl sulphoxide and treated with 11.8 g (132.5 mmol) of sarcosine. The solution is stirred at 100° until the gas evolution ceases (duration: about 1.5 hours) and subsequently poured into about 1.2 l of water. After stirring for 10 minutes, a solid material crystallizes out. The crystals are filtered off under suction, washed with 1 l of water and dried. There is obtained 7-fluoro-3,4-dihydro-4-methyl-2H-1,4-benzodiazepine-2,5(1H)-dione of melting point 262°-263°.

1. stirringAfter stirring for 10 minutes
2. customa solid material crystallizes out
3. filtrationThe crystals are filtered off under suction
4. washwashed with 1 l of water
5. customdried