Trihydroxybenzenes

Trihydroxybenzenes are aromatic compounds in which three hydroxyl groups attach to a single benzene ring, giving the general formula C6H3(OH)3. They are polyphenols related to other di- and tri-hydroxybenzenes and occur in several structural isomers depending on the positions of the hydroxyl substituents. The three distinct isomers are 1,2,3-trihydroxybenzene, 1,2,4-trihydroxybenzene, and 1,3,5-trihydroxybenzene. The 1,2,3- isomer is commonly known as pyrogallol, and the 1,3,5- isomer is commonly known as phloroglucinol; the 1,2,4- isomer is less widely referenced by a universal trivial name.

In nature and industry, tri hydroxybenzenes appear as intermediates in the degradation and transformation of larger polyphenols such as tannins, and they are produced synthetically as building blocks for dyes, pigments, pharmaceuticals, and polymers. They can be obtained by selective hydroxylation or oxidation of related phenols, and by rearrangement routes in phenolic chemistry.

Chemically, these compounds are polar and form extensive hydrogen bonds due to their three hydroxyl groups. They are generally colorless solids or low-melting substances that are soluble to varying degrees in water. They are more reactive toward oxidation than simple phenols and can be converted to quinone or other oxidized species under appropriate conditions. Their reactivity also makes them useful as synthetic intermediates in organic chemistry.

Safety and handling follow the typical precautions for phenolic compounds: they can be irritants and potentially harmful if ingested or absorbed in substantial amounts. Proper PPE and storage away from oxidizing agents are recommended.