反应详情

Dimethyl sulfide (4.4 ml, 60 mmol) and boron trifluoride diethyl etherate (46% purity, 3.3 ml, 12 mmol) were added to a ice cold solution of [rac]-3-(4-benzyloxy-benzofuran-7-yl)-2-ethoxy-propionic acid methyl ester (0.85 g, 2.4 mmol) in dichloromethane (25 ml) under an argon atmosphere. The mixture was stirred for 6 h at ambient temperature, poured into ice water and extracted three times with dichloromethane. The combined extract was washed with brine and dried over sodium sulfate. Removal of the solvent under reduced pressure gave a brown oil which was purified by column chromatography (silica gel, hexane/AcOEt=4/1) to give 0.45 g (1.7 mmol, 71%) of the title compound as light yellow oil.

1. extractionextracted three times with dichloromethane
2. extractionThe combined extract
3. washwas washed with brine
4. dry with materialdried over sodium sulfate
5. customRemoval of the solvent under reduced pressure
6. customgave a brown oil which
7. customwas purified by column chromatography (silica gel, hexane/AcOEt=4/1)