反应详情

Add 0.425 cm3 (4.5 mmol) of tert-butanol to a solution of 0.5 g (2.25 mmol) of ethyl 7-hydroxy-1,4-benzodioxin-2-carboxylate in 3 cm3 of trifluoroacetic acid. The whole is stirred for 24 hours at room temperature and, after concentrating to dryness under reduced pressure, the crude product is then purified by chromatography on a silica column (eluant: petroleum ether/diethyl ether 80:20). Ethyl 7-hydroxy-6-tert-butyl-1,4-benzodioxin-2-carboxylate is obtained in a yield of 78%. Melting point: 222° C. ##STR44##

1. concentrationafter concentrating to dryness under reduced pressure
2. customthe crude product is then purified by chromatography on a silica column (eluant: petroleum ether/diethyl ether 80:20)