反应详情

To a solution of the compound 21 (2.28 g) and triethylamine (4.99 mL) in dimethyl sulfoxide (30 mL), a sulfur trioxide-pyridine complex (2.28 g) was slowly added. The reaction mixture was stirred at room temperature for one hour. To the reaction solution, water (100 mL) was added. The aqueous layer was extracted twice with dichloromethane (50 mL). The combined organic layer was washed with saturated brine, dried over anhydrous magnesium sulfate and then concentrated. The residue was purified by silica gel chromatography (ethyl acetate:methanol:triethylamine=10:1:0→10:1:0.5) to obtain the title compound (2.26 g) having the following physical properties.

1. extractionThe aqueous layer was extracted twice with dichloromethane (50 mL)
2. washThe combined organic layer was washed with saturated brine
3. dry with materialdried over anhydrous magnesium sulfate
4. concentrationconcentrated
5. customThe residue was purified by silica gel chromatography (ethyl acetate:methanol:triethylamine=10:1:0→10:1:0.5)