4-Toluenesulfonyl chloride → (S)-1-Benzyl-3-[(P-tolylsulfonyl)oxy]pyrrolidine

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of (S)-1-benzyl-3-pyrrolidinol (44.3 g, 0.25 mol) and 1,4-diazabicyclo[2.2.2]octane (33.7 g, 0.3 mol) in 250 mL of tert-butyl methyl ether under an atmosphere of nitrogen at 0° C., was added p-toluenesulfonyl chloride (52.4 g, 0.275 mol) portionwise over 20 min. The reaction mixture was stirred at 0° C. for 1 h. The ice bath was then removed and the mixture was stirred at ambient temperature overnight (20±5 h). Ethyl acetate (100 mL) was then added, followed by saturated aqueous sodium bicarbonate solution (250 mL). The resulting mixture was stirred at ambient temperature for 1 h. The layers were separated and the organic layer was washed with saturated aqueous sodium bicarbonate solution (250 mL); saturated aqueous ammonium chloride solution (250 mL); saturated aqueous sodium chloride solution (250 mL); and then dried over sodium sulfate (80 g). The sodium sulfate was filtered off and washed with ethyl acetate (20 mL) and the solvent was removed in vacuo to give 78.2 g of the title intermediate (94% yield; 95% purity by HPLC Method A).

Provenance & Evidence