Sulfonic acid - Wikipedia

A sulfonic acid (or sulphonic acid) refers to a member of the class of organosulfur compounds with the general formula R−S(=O)2−OH, where R is an organic alkyl or aryl group and the S(=O)2(OH) ... HSO3- + RCH=CH2 + H+ → RCH2CH2SO3H: HSO3- + RBr → RSO3H + Br-. Sulfonic acids can be prepared by oxidation of ...