反应详情

To a stirred solution of 4.49 g (21.0 mmol) 18a and 75 ml dichloromethane were added 34.5 g (21.0 mmol) methyltriflate (Aldrich) drop wisely. The reaction mixture was stirred for 2 days at room temperature. 17 g (10 mmol) methyltriflate (Aldrich) were added and the reaction mixture was stirred at 40° C. for 20 h. The reaction mixture was cooled to 20° C. and diethylether was added. The desired compound precipitates and the solvent was decanted and the solid was washed extensively (ten times) with large amounts of diethylether. The solid was dried by use of oil pump vacuum and purified by (C-18) RP-column chromatography (acetonitril/water-gradient 1:99 to 80:20). The desired compound 18b was obtained in 86% yield (6.78 g, 18.1 mmol).

1. stirringthe reaction mixture was stirred at 40° C. for 20 h
2. temperatureThe reaction mixture was cooled to 20° C.
3. customThe desired compound precipitates
4. customthe solvent was decanted
5. washthe solid was washed extensively (ten times) with large amounts of diethylether
6. customThe solid was dried by use of oil pump vacuum
7. custompurified by (C-18) RP-column chromatography (acetonitril/water-gradient 1:99 to 80:20)