反应详情

To 4-hydroxy-α-methylcinnamic acid (55 g), absolute methanol (400 ml) and conc. sulfuric acid (10 ml) were added and refluxed for 12 hours. After the reaction mixture was allowed to cool, it was concentrated under reduced pressure. To the residue was added water (300 ml), and the mixture was neutralized with sodium hydrogen carbonate, and the resulting precipitate was collected by filtration, washed with water, and recrystallized from ethyl acetate/nhexane to give methyl 4-hydroxy-α-methylcinnamate (53 g). mp. 103°-104° C.

1. temperaturerefluxed for 12 hours
2. temperatureto cool
3. concentrationit was concentrated under reduced pressure
4. additionTo the residue was added water (300 ml)
5. filtrationthe resulting precipitate was collected by filtration
6. washwashed with water
7. customrecrystallized from ethyl acetate/nhexane