反应详情

Methyl (Z)-4-benzyloxy-3-(1-methyl-propenyl)-benzoate (592 mg, 2.0 mmol) was dissolved in methanol (20 ml), a solution of potassium hydroxide (336 mg, 6.0 mmol) in water (7 ml) was added and the mixture was stirred and held at reflux for 3 hours. Upon cooling the solvent was removed in vacuo and the mixture acidified to pH 2 or below by the addition of 2M hydrochloric acid. The mixture was extracted with dichloromethane, the organic layer was separated and the solvent removed in vacuo to afford (Z)-4-benzyloxy-3-(1-methyl-propenyl)-benzoic acid (460 mg, 82%) as a colourless solid. 1H NMR (DMSO-d6) 7.85 (1H, dd), 7.57 (1H, d), 7.40 (4H, m), 7.34 (1H, m), 7.18 (1H, d), 5.57 (1H, q), 5.21 (2H, s), 1.96 (3H, s), 1.40 (3H, d). MS: [M+H]+ 283.

1. temperatureat reflux for 3 hours
2. temperatureUpon cooling the solvent
3. customwas removed in vacuo
4. additionthe mixture acidified to pH 2 or below by the addition of 2M hydrochloric acid
5. extractionThe mixture was extracted with dichloromethane
6. customthe organic layer was separated
7. customthe solvent removed in vacuo