(Diethylamino)sulfur trifluoride → HCID 14612530, compound

(3R,4R)-3-Azidomethyl-1-benzyl-4-hydroxypyrrolidine (566 mg) was dissolved in dichloromethane (9 mL). While this solution was cooled on an ice bath, diethylaminosulfur trifluoride (0.39 mL) was added dropwise and the mixture was stirred at room temperature for 2 hours. While the reaction vessel was cooled on an ice bath, a saturated aqueous solution of sodium hydrogen carbonate (9 mL) was added, and the mixture was diluted with dichloromethane (15 mL). The dichloromethane layer was collected and the collected dichloromethane layer was washed with a saturated aqueous solution of sodium hydrogen carbonate (10 mL) and then water (10 mL), was dried over anhydrous sodium sulfate, and was concentrated under reduced pressure. The resulting residue was purified on a silica gel column (eluant=hexane:ethyl acetate=4:1). From the first half fraction, 76.7 mg of (3R,4R)-3-azidomethyl-1-benzyl-4-fluoropyrrolidine was obtained as a pale brown oil.