(Diethylamino)sulfur trifluoride → (3S,4S)-1-benzyloxycarbonyl-3-bromomethyl-4-fluoropyrrolidine

Process A: (3S,4R)-1-Benzyloxycarbonyl-3-bromomethyl-4-hydroxypyrrolidine (2.70 g) was dissolved in dichloromethane (60 mL). While the solution was chilled in an ice water bath, diethylaminosulfur trifluoride (2.30 mL) was added dropwise and the mixture was stirred at room temperature for 20 hours. Following addition of a saturated aqueous solution of sodium bicarbonate (30 mL) in an ice water bath, the dichloromethane layer was separated. The dichloromethane layer was washed sequentially with a saturated aqueous solution of sodium bicarbonate (30 mL) and saturated brine (30 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluant: hexane: ethyl acetate=2:1) to give (3S,4S)-1-benzyloxycarbonyl-3-bromomethyl-4-fluoropyrrolidine as a yellow-brown tar (2.20 g).

1. temperatureWhile the solution was chilled in an ice water bath
2. customthe dichloromethane layer was separated
3. washThe dichloromethane layer was washed sequentially with a saturated aqueous solution of sodium bicarbonate (30 mL) and saturated brine (30 mL)
4. dry with materialdried over anhydrous sodium sulfate
5. concentrationconcentrated under reduced pressure
6. customThe resulting residue was purified by silica gel column chromatography (eluant: hexane: ethyl acetate=2:1)

ORD record

ord-b0383d01513b4f1297c4ddb4f5df9e3a

Source dataset

uspto-grants-2009_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07514451B2