Toluene → tert-Butyl(3R)-3-fluoromethyl-4-methyl-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

Tert-butyl(3S)-3-hydroxymethyl-4-methyl-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylate (1.70 g, 5.10 mmol) was dissolved in dichloromethane (20 mL). To this solution, toluene (20 mL) was added, and diethylaminosulfur trifluoride (1.68 mL, 12.8 mmol) was added dropwise in an ice bath. After stirring at 60° C. for 8 hours, saturated aqueous solution of sodium hydrogencarbonate (50 mL) was added to the reaction mixture, and the mixture was extracted by ethyl acetate (100 mL×2). The organic layer was washed with saturated aqueous solution of sodium chloride (100 mL), and dried with anhydrous sodium sulfate. After filtration, the filtrate was concentrated under reduced pressure. The concentrate was then purified by silica gel column chromatography (solution by hexane:ethyl acetate, 9:1→2:3) to obtain 0.910 mg (53%) of the title compound as a pale yellow oily substance.

Provenance & Evidence