反应详情

温度

100 °C

2-Amino-5-methylpyridine (21.6 g.) is added to a suspension of pyrazine-2,3-dicarboxylic anhydride (30 g.) in acetic anhydride (300 cc.) at a temperature of about 25° C. The reaction mixture is stirred for 10 minutes at this temperature and then heated at a temperature of about 100° C. for 15 minutes. After cooling to a temperature of about 50° C., diisopropyl ether (600 cc.) is added and cooling is continued to 5° C. After stirring for one hour at this temperature, the insoluble product is filtered off and washed with diisopropyl ether (3×50 cc.). After drying, 6-(5-methylpyrid-2-yl)-5,7-dioxo-6,7-dihydro-5H-pyrrolo-[3,4-b]pyrazine (32 g.), which melts at 240° C., is obtained.

1. additionis added
2. temperaturecooling
3. customis continued to 5° C
4. stirringAfter stirring for one hour at this temperature
5. filtrationthe insoluble product is filtered off
6. washwashed with diisopropyl ether (3×50 cc.)
7. customAfter drying