反应详情

A reaction mixture containing m-nitrobenzaldehyde (151 g; 1.0 mole), ethyl acetoacetate (130 g; 1.0 mole), piperidine (4 mL) and glacial acetic acid (12 mL) in 200 mL benzene was refluxed for 2.5 hr while removing water (19 mL) by means of a Dean Stark trap. The dark brown reaction solution was allowed to cool to room temperature and was then water washed several times and concentrated in vacuo to give a dark yellow solid. This solid was recrystallized from ethanol to yield 182 g (69% yield) of yellow solid, m.p. 103°-106° C. Literature m.p.: S. Ruhemann, J. Chem. Soc., Vol 83, 717 (1903)--m.p. 110° C.

1. temperaturewas refluxed for 2.5 hr
2. customwhile removing water (19 mL) by means of a Dean Stark trap
3. concentrationwater washed several times and concentrated in vacuo
4. customto give a dark yellow solid
5. customThis solid was recrystallized from ethanol