Sulfuric Acid → 6-Methoxy-benzofuran-2,3-dicarboxylic acid diethyl ester

Participants

Reaction Steps

2-(3-Methoxy-phenoxy)-3-oxo-succinic acid diethyl ester (23) (60 g, 193.4 mmol) is dissolved in 32 ml of cooled (−15° C.) cone, sulfuric acid and stirred for 3 h whereas the reaction mixture slowly warmed up to room temperature. Then the mixture is poured onto 1 kg of ice and extracted with diethyl ether. The organic layers are washed with brine, dried over sodium sulfate, filtrated and evaporated. The crude product is purified by Flash-chromatography (silica gel, ethyl acetate/hexanes 1:9).

Provenance & Evidence