4-Toluenesulfonyl chloride → (R)-Toluene-4-sulfonic acid 2-(6-chloro-pyridin-3-yl)-2-hydroxy-ethyl ester

Participants

Reaction Conditions

Reaction Steps

To a cooled (50° C.), stirred solution of (R)-1-(6-chloro-pyridin-3-yl)-ethane-1,2-diol (17.8 g) in anhydrous pyridine (100 mL) was added p-toluenesulfonyl chloride (19.5 g) in one portion. After 20 min, the cooling bath was removed and stirring was continued an additional 2 h. The reaction solution was concentrated in vacuo, azeotroped with toluene (2×), diluted in ethyl acetate, washed with half-saturated aqueous brine, saturated aqueous brine, dried over sodium sulfate and concentrated in vacuo. The resulting solids were recrystallized from ethyl acetate/hexanes to afford 23.3 g of the title compound (I-2d) as colorless crystals.

Provenance & Evidence