Catechol

Catechol, also known as pyrocatechol, is an organic compound with the formula C6H4(OH)2. It is a dihydroxybenzene in which the two hydroxyl groups are adjacent on the benzene ring (ortho configuration). In its pure form it is a colorless to pale yellow solid that is soluble in water and many organic solvents. Catechol readily oxidizes in air to o-benzoquinone and can undergo further oxidation and polymerization to brown, pigment-like materials.

Structure and reactivity: The ortho-dihydroxy arrangement gives catechol strong reducing properties and a tendency to form complexes with metal ions. It can act as a ligand, and its oxidation products, such as o-quinones, participate in various chemical reactions. Catechol is often used as a building block in organic synthesis and as a reducing agent in analytical and industrial contexts.

Occurrence and production: Catechol occurs only in trace amounts in nature. Commercially it is produced as a chemical intermediate for the manufacture of polymers, dyes, flavors and fragrances, and pharmaceutical precursors. It can be generated via different industrial routes that introduce the ortho-dihydroxy functionality into benzene derivatives or through oxidation of related phenolic compounds.

Uses: It serves as a versatile intermediate for the synthesis of catechol-based resins, dyes, and specialty chemicals. Its redox properties also make it useful in analytical chemistry and as a reagent in various organic transformations.

Safety and handling: Catechol is a skin and eye irritant and can be harmful if inhaled or ingested. It should be handled with appropriate protective equipment in a well-ventilated area, and wastes should be disposed of according to relevant regulations. It is reactive toward air and should be stored away from oxidizable materials.