反应详情

(2S)-1-[2-(benzenesulfonyloxy)acetyl]-4,4-difluoropyrroli dine-2-carboxamide (872 mg) was dissolved in acetonitrile (16 mL), followed by triethylamine (1.05 mL). While this mixture was cooled in a salt-ice bath, trifluoroacetic anhydride (0.53 mL) was added dropwise. The mixture was stirred at the same temperature for 1 hour, followed by the addition of water (16 mL) and extraction with ethyl acetate (2×60 mL). The ethyl acetate extracts were combined, washed with saturated brine (2×20 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The resulting residue was purified on a silica gel column (eluant=hexane:ethyl acetate=1:1) to give (2S)-1-[2-(benzenesulfonyloxy)acetyl]-4,4-difluoropyrrolidine-2-carbonitrile as a white crystal (789 mg, 96% yield).

1. temperatureWhile this mixture was cooled in a salt-ice bath
2. washwashed with saturated brine (2×20 mL)
3. dry with materialdried over anhydrous sodium sulfate
4. concentrationconcentrated under reduced pressure
5. customThe resulting residue was purified on a silica gel column (eluant=hexane:ethyl acetate=1:1)