Methanesulfonyl chloride can be used for the mesylation of primary alcohols to synthesize the corresponding methanesulfonates. It may also be used for the conversion of amines to the corresponding sulfonamides.
rylsulfonyl chlorides are made industrially in a two-step, one-pot reaction from the arene and chlorosulfuric acid: C6H6 + HOSO2Cl → C6H5SO3H + HCl. Phenyldiazonium chloride reacts with sulfur dioxide and hydrochloric acid to give the sulfonyl chloride: