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 DABCO (33.7 g, 0.3 mol) in MTBE (250 mL) under an atmosphere of nitrogen at 0° C., was added p-toluenesulfonyl chloride (52.4 g, 0.275 mol) portionwise over 20 minutes. The reaction mixture was stirred at 0° C. for 1 hour. The ice bath was removed and the mixture was stirred at ambient temperature overnight (20±5 hours). EtOAc (100 mL) was added, followed by saturated aqueous sodium bicarbonate solution (250 mL). The resulting mixture was stirred at ambient temperature for 1 hour. 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 NaCl solution (250 mL); and then dried over sodium sulfate (80 g). The sodium sulfate was filtered off and washed with EtOAc (20 mL) and the solvent was removed in vacuo to give 78.2 g of the title intermediate as an off-white solid (94% yield; 95% purity by HPLC).

Provenance & Evidence