反应详情

To a solution of (2RS,3RS)-3-[4-(methylsulfonyl)phenyl]-3-hydroxy-2-[3-(1,1,2,2-tetrafluoroethoxy)benzyl]propanoic acid (2.20 g, 4.88 mmol) in tetrahydrofuran (20 ml) were added diphenylphosphoryl azide (1.37 ml, 6.35 mmol) and triethylamine (0.95 ml, 6.84 mmol) and the mixture was stirred at room temperature for 1 hr. After heating under reflux for 1 hr, water (100 ml) was added and the mixture was extracted, with ethyl acetate (100 ml×2). The extract was washed with saturated aqueous sodium hydrogen carbonate solution, dried over anhydrous magnesium sulfate and evaporated under reduced pressure. The residue was purified by silica gel chromatography (hexane:ethyl acetate=1:1-1:3). Hexane was added to the precipitated crystals and the mixture was filtered to give the objective substance (2.07 g, 95%).

1. temperatureAfter heating
2. temperatureunder reflux for 1 hr
3. extractionthe mixture was extracted, with ethyl acetate (100 ml×2)
4. washThe extract was washed with saturated aqueous sodium hydrogen carbonate solution
5. dry with materialdried over anhydrous magnesium sulfate
6. customevaporated under reduced pressure
7. customThe residue was purified by silica gel chromatography (hexane:ethyl acetate=1:1-1:3)
8. additionHexane was added to the precipitated crystals
9. filtrationthe mixture was filtered
10. customto give the objective substance (2.07 g, 95%)