反应详情

1.9 pts. by wt. of 5-bromofurfural, 1.3 pts. by wt. of 1-amino-2,3-dioxo-piperazine and 7 pts. by vol. of glacial acetic acid were warmed to 90° for 10 minutes and then left for 30 minutes at RT. The precipitate is filtered off, washed with 3 pts. by vol. of glacial acetic acid and recrystallised from dimethylformamide, with the addition of animal charcoal. 1.1 pts. by wt. (38.5%) of 1-(5-bromofurfurylideneamino)-2,3-dioxo-piperazine are obtained as yellowish crystals of decomp. pt. 220°.

1. filtrationThe precipitate is filtered off
2. washwashed with 3 pts
3. customby vol. of glacial acetic acid and recrystallised from dimethylformamide, with the addition of animal charcoal