反应详情

3-tert-butyl-4-hydroxy-5-iodobenzaldehyde (24.8 gm), malononitrile (6.2 gm), piperidine (1.0 ml), acetic acid (3.3 ml) and benzene (300 ml) were refluxed under a Dean and Stark water separator for 2 hours. On cooling a crystalline precipitate formed and was filtered off. Recrystallisation from ethylene dichloride gave pale yellow needles of 3-tert-butyl-4-hydroxy-5-iodobenzylidenemalononitrile (24.2 gm) m.p. 188°.

1. temperatureOn cooling a crystalline precipitate
2. customformed
3. filtrationwas filtered off
4. customRecrystallisation from ethylene dichloride