Allyl bromide → Methyl 3-(Allyloxy)-5-methoxybenzoate
Reaktionsgleichung
[CH3:1][O:2][C:3](=[O:13])[C:4]1[CH:9]=[C:8]([O:10][CH3:11])[CH:7]=[C:6]([OH:12])[CH:5]=1.[CH2:14](Br)[CH:15]=[CH2:16].C(=O)([O-])[O-].[K+].[K+]>>[CH3:1][O:2][C:3](=[O:13])[C:4]1[CH:9]=[C:8]([O:10][CH3:11])[CH:7]=[C:6]([O:12][CH2:16][CH:15]=[CH2:14])[CH:5]=1Komponenten
4
Versuchsvorschrift
3-Hydroxy-5-methoxybenzoic acid methyl ester is reacted with allyl bromide in the presence of potassium carbonate to give 3-allyloxy-5-methoxybenzoic acid methyl ester. B.p. 128°-30°C/0.4 mmHg. The ester is hydrolized to the corresponding acid with 20% potassium hydroxide in aqueous ethanol. The acid (m.p. 85°-7°C) when heated for 2 hours at 230°C undergoes Claisen rearrangement and cyclization to the title compound which melts at 195°-7°C.