反应详情

A mixture of 35.1 g (0.29 mol) of o-tolualdehyde, 47.6 g (0.46 mol) of acetic anhydride, and 18 g (0.174 mol) of fused and pulverized potassium acetate was heated at 155°-160° for 15 minutes and then at 165°-170° for 12 hours. The mixture was diluted with 1 liter of ice water and steam distilled to remove excess aldehyde. On cooling, a yellow solid formed. The solid was collected, washed with water, dissolved in chloroform, treated with charcoal, and filtered. The filtrate was concentrated and the residue was recrystallized from ethanol/ether to give 16.5 g (35%) of trans-2-methylcinnamic acid; mp 173°-175°.

1. temperaturewas heated at 155°-160° for 15 minutes
2. distillationdistilled
3. customto remove excess aldehyde
4. temperatureOn cooling
5. customa yellow solid formed
6. customThe solid was collected
7. washwashed with water
8. dissolutiondissolved in chloroform
9. additiontreated with charcoal
10. filtrationfiltered
11. concentrationThe filtrate was concentrated
12. customthe residue was recrystallized from ethanol/ether