反应详情

Stir for 3 hours, at room temperature and under a nitrogen atmosphere, a mixture of 16 g (43.7 mmol) of ethyl 2,3-dibromo-1,4-benzodioxin-2-carboxylate and 24 g (160 mmol) of sodium iodide in 80 cm3 of anhydrous acetone. The reaction mixture is then concentrated under reduced pressure, hydrolysed with 80 cm3 of water, and subsequently extracted with diethyl ether. After treatment with an aqueous sodium thiosulfate solution followed by drying over magnesium sulfate, the ethereal phase is concentrated to dryness under reduced pressure and the crude product is purified by chromatography on a silica column (eluant: petroleum ether/diethyl ether, 40:60). Ethyl 1,4-benzodioxin-2-carboxylate is thereby obtained in a yield of 85%. Melting point: 42° C. ##STR29##

1. concentrationThe reaction mixture is then concentrated under reduced pressure, hydrolysed with 80 cm3 of water
2. extractionsubsequently extracted with diethyl ether
3. dry with materialby drying over magnesium sulfate
4. concentrationthe ethereal phase is concentrated to dryness under reduced pressure
5. customthe crude product is purified by chromatography on a silica column (eluant: petroleum ether/diethyl ether, 40:60)