反应详情

A mixture of 3-fluorobenzaldehyde (40 g), malonic acid (47 g), and an ethanolic solution (150 ml) containing pyridine (10 g) and piperidine (5 g) was heated at reflux with stirring for 8 hours. The reaction mixture was chilled and water (300 ml) was added, giving crystalline trans 3-fluorocinnamic acid which was removed by filtration, washed with water and dried. The trans 3-fluorocinnamic acid, m.p. 162°-163° C., was obtained in 84% yield (44.6 g).

1. temperaturewas heated
2. temperatureat reflux
3. temperatureThe reaction mixture was chilled