Chlorosulfonic acid → 2,5-Dichloro-4-methylbenzene-1-sulfonyl chloride
Reaction equation
[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([Cl:8])=[CH:4][C:3]=1[CH3:9].[Cl:10][S:11](O)(=[O:13])=[O:12]>>[Cl:8][C:5]1[CH:4]=[C:3]([CH3:9])[C:2]([Cl:1])=[CH:7][C:6]=1[S:11]([Cl:10])(=[O:13])=[O:12]Participants
3
Conditions
- Temperature
- 0 °C
Procedure
A dry flask under argon was charged with chlorosulfonic acid (30 mL) and cooled to 0° C. 2,5-Dichlorotoluene (10 g, 62.1 mmol) was then added dropwise, and once the addition was complete, the reaction was heated to 60° C. and stirred for 30 min. After cooling to room temperature, the reaction mixture was poured slowly onto ice. The aqueous mixture was extracted twice with methylene chloride, and the organics were dried and concentrated to provide 2,5-dichloro-4-methylbenzenesulfonyl chloride (14.14 g, 88%) as a white solid.