2,4-Dichlorophenol → 3,5-Dichloro-2-hydroxybenzenesulphonyl chloride

Participants

Reaction Conditions

Reaction Steps

Molten 2,4-dichlorophenol (82.7 g) was contacted with 166 ml of chlorosulfonic acid at 37°-40° C. over a 1 hour period. After a 15 minute hold at 40° C. the reaction was cooled to 25° C. and 73 ml of SOCl2 was added. The temperature was raised to 32° C. for 40 minutes and then allowed to cool to 25° C. over 1 hour. The reaction mixture was quenched onto ice. Filtration and drying afforded 126.7 g of 99% pure 2-hydroxy-3,5-dichlorobenzenesulfonyl chloride (C) (94% yield).

Provenance & Evidence