sulfonic acid n.
Any of several organic acids containing one or more sulfonic groups.
|sulfonic acid (sŭl-fŏn'ĭk) Pronunciation Key
Any of several acids containing the group SO3H attached to an organic radical. Sulfonic acids and their salts are important in industry as catalysts in organic synthesis and in making sulfonamide drugs, detergents, and dyes.
any of a class of organic acids containing sulfur and having the general formula RSO3H, in which R is an organic combining group. The sulfonic acids are among the most important of the organosulfur compounds; the free acids are widely used as catalysts in organic syntheses, while the salts and other derivatives form the basis of the manufacture of detergents, water-soluble dyes and catalysts, sulfonamide pharmaceuticals, and ion-exchange resins. Aromatic sulfonic acids are particularly useful as intermediates or starting materials in synthesis-for example, in the preparation of phenols. Sulfonic acid groups can greatly enhance the water solubility of compounds, as seen with the sulfonic acid derivative of triphenyl phosphine (TPPTS), P(C6H4-m-SO3Na)3. Metal complexes of this compound are used as homogeneous catalysts for the syntheses of organic compounds in two-phase systems (e.g., in a mixture of water and an organic solvent) in industry and in the laboratory.
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