反应详情

(R)-N-((S)-2-(5-bromo-2-fluoropyridin-3-yl)-1,5,5,5-tetrafluoro-4-oxopentan-2-yl)-2-methylpropane-2-sulfinamide (6.32 g, 14.01 mmol) was dissolved in anhydrous methanol 75 mL and the solution was cooled in an ice bath. Sodium tetrahydroborate (0.795 g, 21.01 mmol) was added portionwise as solid. After stirring in the ice bath for 10 min, the reaction was worked up with saturated sodium bicarbonate and extracted with EtOAc three times. The combined organic layers were washed with brine and dried over sodium sulfate, filtered and concentrated. The crude material was purified by column chromatography using a gradient of 15-50% EtOAc/hexane to give (R)-N-((2S,4S)-2-(5-bromo-2-fluoropyridin-3-yl)-1,5,5,5-tetrafluoro-4-hydroxypentan-2-yl)-2-methylpropane-2-sulfinamide (12e, 3.68 g, 58% yield). MS m/z=454.9 [M+H]+. Calculated for C14H18BrF5N2O2S: 453.3; and (R)-N-((2S,4R)-2-(5-bromo-2-fluoropyridin-3-yl)-1,5,5,5-tetrafluoro-4-hydroxypentan-2-yl)-2-methylpropane-2-sulfinamide (1.5 g, 24% yield). MS m/z=454.9 [M+H]+. Calculated for C14H18BrF5N2O2S: 453.3.

1. temperaturethe solution was cooled in an ice bath
2. extractionextracted with EtOAc three times
3. washThe combined organic layers were washed with brine
4. dry with materialdried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated
7. customThe crude material was purified by column chromatography