反应详情

A suspension of 11.0 g (40.7 mmole) of ethyl 4,5-dihydro-5-methyl-4-oxopyrano[3,2-b]indole-2-carboxylate in 500 ml ethanol was stirred in ice while gaseous ammonia was added until the reaction mixture temperature reached 20° C. (ca. 10 min). The ice bath was removed, and stirring at room temperature was continued for a total of 24 hr. The light yellow solid was filtered and washed with a little cold ethanol. Recrystallization from 50% aqueous DMF gave light yellow needles of mp >295° C.

1. additionwas added until the reaction mixture temperature
2. customreached 20° C.
3. custom(ca. 10 min)
4. customThe ice bath was removed
5. customwas continued for a total of 24 hr
6. filtrationThe light yellow solid was filtered
7. washwashed with a little cold ethanol
8. customRecrystallization from 50% aqueous DMF
9. customgave light yellow needles of mp >295° C.