Main Uses

Chlorinating agent in organic synthesis:

Used for electrophilic substitution reactions of aromatic compounds to achieve the substitution of hydrogen on the benzene ring with chlorine (e.g., preparation of chlorinated aromatics).

As a chlorinating reagent for alkanes and alkenes; for example, in the presence of light or catalysts (such as benzoyl peroxide), it undergoes radical substitution reactions with alkanes to generate chlorinated alkanes.

Sulfonation and chlorosulfonation reagent:

Used for the preparation of sulfonyl chloride compounds (e.g., aromatic sulfonyl chlorides), which are important intermediates in the synthesis of sulfonamide drugs and dyes.

In the rubber industry, used for the chlorosulfonation of rubber to improve its weather resistance and oil resistance. Other applications:

As a disinfectant and fumigant (due to the decomposition producing chlorine gas and sulfur dioxide, which have bactericidal effects). Used for the preparation of ion exchange resins, surfactants, etc.

In the laboratory, used as an alternative reagent for chlorination reactions, offering easier control than chlorine gas.