反应详情

Methyl 4-acetoxy-3-thiophenecarboxylate (81 g, 0.40 mol) and concentrated sulphuric acid (5 ml) in methanol (1.25 l) was heated under reflux for 3 days. The solvent was evaporated and the residue diluted with water (300 ml) and extracted with ether (5 times). The ether extracts were combined, washed with 1N sodium hydroxide (3 times) and dried over sodium sulfate. Evaporation of the solvent gave the title compound, 52 g, m.p. 66°-68° (lit. m.p.68°-70°).

1. temperatureunder reflux for 3 days
2. customThe solvent was evaporated
3. additionthe residue diluted with water (300 ml)
4. extractionextracted with ether (5 times)
5. washwashed with 1N sodium hydroxide (3 times)
6. dry with materialdried over sodium sulfate
7. customEvaporation of the solvent