4-Toluenesulfonyl chloride → (2R,4R)-1-(Toluene-4-sulfonyl)-4-(toluene-4-sulfonyloxy)-pyrrolidine-2-carboxylic Acid Ethyl Ester

Participants

Reaction Conditions

Reaction Steps

To a cold solution of 4-hydroxy-pyrrolidine-2-carboxylic acid ethyl ester (1) (1.4 g, 7.1 mmol) and triethyl amine (0.998 mL, 7.1 mmol) in pyridine (14 mL) at −5° C. was added portion-wise 4-toluenesulfonyl chloride (3.42 g, 17.9 mmol). The cold solution was then stirred for 1 h at 0° C. and stored overnight in the refrigerator. Then the mixture was further stirred at room temperature for 5 h and poured into ice water (10 mL). The precipitate separated out was filtered, washed with water (2×5 mL), and dried to give compound (2) as a white solid.

Provenance & Evidence