反应详情

Ex-1A: Catechol (2.2 g, 20 mmol) was dissolved in acetone. Diethyl dibromomalonate (7.0 g, 22 mmol) and potassium carbonate (2.76 g) were added, and the mixture was stirred at room temperature overnight. The solvent was removed under reduced pressure, and water was added to the residue. The residue was extracted with dichloromethane, and the organic phase was washed with brine, dried over magnesium sulfate and evaporated. Chromatography (hexanes/ethyl acetate, 4:1) gave 3.9 g of benzo[1,3]dioxole-2,2-dicarboxylic acid diethyl ester. 1H-NMR (CDCl3) δ 6.90–6.97 (m, 4H), 4.37 (q, J=7 Hz, 4H), 1.32 (t, J=7 Hz, 6H).

1. customThe solvent was removed under reduced pressure, and water
2. additionwas added to the residue
3. extractionThe residue was extracted with dichloromethane
4. washthe organic phase was washed with brine
5. dry with materialdried over magnesium sulfate
6. customevaporated