Benzenesulfonyl chloride → (3S)-3-(3-benzenesulfonyloxy-1-propyl)-4-Fluoro-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylic acid tert-butyl ester

Participants

Reaction Steps

(3S)-4-Fluoro-3-(3-hydroxy-1-propyl)-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylic acid tert-butyl ester (12.20 g) was dissolved in dichloromethane (400 mL). Benzenesulfonyl chloride (9.06 mL), triethylamine (10.7 mL), and 4-dimethylaminopyridine (2.04 g) were added under ice-cooling, and the mixture was stirred at room temperature for 12.5 hours. Saturated sodium bicarbonate water was added to the reaction solution, and the mixture was stirred for 30 minutes, followed by extraction with dichloromethane. The organic layer was sequentially washed with a 10% citric acid solution and brine, dried over anhydrous sodium sulfate, and filtered. Thereafter, the solvent was evaporated under reduced pressure. The residue was subjected to silica gel column chromatography (hexane:ethyl acetate=8:2→1:1) to give 11.7 g of the title compound as a pale yellow oil.

Provenance & Evidence