4-Chlorobenzoic Acid → 4-Chloro-3-(chlorosulphonyl)benzoic acid

Participants

Reaction Steps

At 5-10° C., to stirred chlorosulfonic acid (200 mL) was added 4-chlorobenzoic acid (78 g, 0.5 mol). The reaction mixture was then brought up to 150˜160° C. for 5 hours. After being cooled down to room temperature, the reaction mixture was slowly poured onto a large amount of ice and extracted with ether. The combined organic extracts were washed with ice water and dried over anhydrous magnesium sulfate. Evaporation of solvents afforded 4-chloro-3-(chlorosulfonyl)benzoic acid as a solid (76 g), which was directly used in the next steps.

Provenance & Evidence