C6H6O9S3

C6H6O9S3 is the chemical formula for benzene-1,3,5-trisulfonic acid. This compound is a tri-sulfonated derivative of benzene. It is a strong acid due to the presence of three sulfonic acid groups attached to the benzene ring. These sulfonic acid groups are electron-withdrawing, which increases the acidity of the molecule. Benzene-1,3,5-trisulfonic acid is typically a solid at room temperature. It is soluble in water and polar organic solvents.

The synthesis of benzene-1,3,5-trisulfonic acid is usually achieved through the direct sulfonation of benzene. This reaction typically requires harsh conditions, such as concentrated sulfuric acid or fuming sulfuric acid (oleum), and elevated temperatures. The trisulfonation occurs at the meta positions (1, 3, and 5) due to the deactivating and meta-directing nature of the sulfonic acid groups as they are introduced.

Benzene-1,3,5-trisulfonic acid finds applications as a strong acid catalyst in various organic reactions, particularly in electrophilic aromatic substitution reactions where a strong acidic environment is required. Its high acidity and water solubility make it a useful reagent in aqueous or polar media. It can also be used in the preparation of other specialty chemicals and in certain analytical procedures. The compound's stability and acidic properties are key to its utility in chemical processes.