反应详情

1.3 pts. by wt. of 1-amino-2,3-dioxo-piperazine, 1.3 pts. by wt. of benzaldehyde and 7 pts. by vol. of glacial acetic acid are warmed to 90° for 90 minutes and then left at 5° for 30 minutes. The precipitate is filtered off, washed first with 3 pts. by vol. of glacial acetic acid and then with three times 10 pts. by vol. of ethyl acetate and dried over P2O5. 1.75 pts. by wt. (81.8% ) of 1-benzylideneamino-2,3-dioxo-piperazine of melting point 236°-240° C. are obtained.

1. filtrationThe precipitate is filtered off
2. washwashed first with 3 pts
3. dry with materialby vol. of ethyl acetate and dried over P2O5