反应详情

To a solution of 3,4-methylenedioxyphenylacetic acid (4.2 g, 23 mmol) in methanol (50 mL) was added concentrated sulfuric acid (1.5 mL). The mixture was refluxed for 48 h, cooled to room temperature, and neutralized with saturated NaHCO3. The methanol was removed in vacuo. The residue was extracted with 1:1 hexane/EtOAc (2×100 mL). The combined organic phase was washed with water, saturated NaHCO3, and brine, and dried over Na2SO4. The solvent was removed in vacuo to yield the title compound as an oil (3.9 g, 86%). 1H NMR (CDCl3) 6.78-6.72 (m, 3H), 5.95 (s, 2H), 3.69 (s, 3H), 3.54 (s, 2H).

1. temperatureThe mixture was refluxed for 48 h
2. customThe methanol was removed in vacuo
3. extractionThe residue was extracted with 1:1 hexane/EtOAc (2×100 mL)
4. washThe combined organic phase was washed with water, saturated NaHCO3, and brine
5. dry with materialdried over Na2SO4
6. customThe solvent was removed in vacuo