反应详情

A solution of 3-fluoro-4-hydroxy-benzoic acid (5.16 g, 33.1 mmol) in ethanol (100 ml) was treated with conc. sulphuric acid (5 ml), and the mixture heated at reflux for 4 days. The volatiles were removed in vacuo, and the aqueous residue was basified with saturated NaHCO3 and extracted twice with diethyl ether. The combined organic extracts were dried and concentrated in vacuo to yield the title compound (5.16 g, 85%).

1. temperaturethe mixture heated
2. temperatureat reflux for 4 days
3. customThe volatiles were removed in vacuo
4. extractionextracted twice with diethyl ether
5. customThe combined organic extracts were dried
6. concentrationconcentrated in vacuo