反应详情

Acetic anhydride (3.06 g, 30.0 mmol) was added to methyl 2,4-dihydroxybenzoate (5.04 g, 30.0 mmol) in boron trifluoride diethyl etherate (7.6 ml) and the mixture was stirred and held at reflux for 3 hours and then allowed to cool to room temperature. Water (80 ml) was added and the mixture stirred at room temperature for 30 minutes. The resulting yellow solid was removed by filtration and sucked as dry as possible under vacuum. The solid was dissolved in dichloromethane and was washed with water, the organic layer was separated and the solvent removed in vacuo to afford methyl 5-acetyl-2,4-dihydroxybenzoate as a bright yellow solid (2.62 g, 42%) which was used without further purification. 1H NMR (DMSO-d6) 12.58 (1H, s), 11.22 (1H, s), 8.33 (1H, s), 6.45 (1H, s), 3.90 (3H, s), 2.62 (3H, s). MS: [M+H]+ 211.

1. temperatureat reflux for 3 hours
2. stirringthe mixture stirred at room temperature for 30 minutes
3. customThe resulting yellow solid was removed by filtration
4. customas dry as possible under vacuum
5. dissolutionThe solid was dissolved in dichloromethane
6. washwas washed with water
7. customthe organic layer was separated
8. customthe solvent removed in vacuo