Benzyl Chloride → HCID 69686559, compound

Participants

Reaction Steps

A solution (100 ml) of 8.816 g (39.1 mmol) of 3-[(1R,2S)-2-t-butoxycarbonylcylcopropyl]pyrrolidin-2-one in a 3:2 mixed solvent of tetrahydrofuran and dimethylformamide was added dropwise to 20 ml of a suspension of 1.72 g (43.0 mmol) of sodium hydride in dimethylformamide while cooling with ice, and the mixture was stirred at room temperature for 1.5 hours. Then, 40 ml of a tetrahydrofuran solution of 6.76 ml (58.7 mmol) of benzyl chloride was added dropwise thereto, followed by stirring for 3 hours. After completion of the reaction, a saturated ammonium chloride aqueous solution was added thereto, followed by evaporation under reduced pressure. Water was added to the residue, and the mixture was extracted with ethyl acetate. The organic layer was washed with water and then with a saturated sodium chloride aqueous solution. The organic layer was dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=7:3) to give 5.710 g (44.8%) of 1-benzyl-3-[(1R,2S)-2-t-butoxycarbonylcyclopropyl]pyrrolidin-2-one (isomer A1) as a colorless solid. Then, the column was eluted with a 1:1 mixed solvent of hexane and ethyl acetate to give 3.959 g (31.1%) of 1-benzyl-3-[(1R,2S)-2-t-butoxycarbonylcyclopropyl]pyrrolidin-2-one (isomer B1) as a pale yellow oily substance.

Provenance & Evidence