1,2,4-Benzenetriol

Gray powder

1,2,4-Benzenetriol forms colorless platelets or prisms that quickly colorize in air. It is soluble in water and polar solvents, and slightly soluble in chloroform and carbon disulfide.

1,2,4-Trihydroxybenzene is an important raw material and intermediate used in organic Synthesis, pharmaceuticals, agrochemicals and dyestuff.It is used as a metabolite of benzene.

ChEBI: Benzene-1,2,4-triol is a benzenetriol carrying hydroxy groups at positions 1, 2 and 4. It has a role as a mouse metabolite.

1,2,4-Benzenetriol is synthesized by hydrolysis of 1,2,4-triacetoxybenzene, which is prepared by the acid-catalyzed reaction of p-benzoquinone with acetic anhydride.
Other production methods for 1,2,4-Benzenetriol are oxidation of resorcinol with hydrogen peroxide and Dakin oxidation of 2,4- or 3,4-dihydroxybenzaldehydes or 2,4- or 3,4-dihydroxyacetophenones with alkaline hydrogen peroxide solution.

1,2,4-Benzenetriol is also known as hydroxyhydroquinone. It is an intermediary metabolite of benzene that is present in roasted coffee beans. It is mutagenic and it causes cleaving of DNA single strands by the generation of reactive oxygen species.

1,2,4-Benzenetriol is, like other phenols, a strong reducing agent. Its basic aqueous solution absorbs gaseous oxygen to produce black precipitates of the humic acid type. 1,2,4-Benzenetriol shows typical reactions of phenols. Derivatives of the tautomeric keto form are also known: halogenation of hydroxyhydroquinone, for example, gives 1,2,5,5-tetrahalocyclohexene-3,4,6-trione. Condensation with ethylacetoacetate produces dihydroxycoumarin; reaction with phthalic anhydride yields hydroxyhydroquinonephthalein. Monosubstitution of a hydroxy group by an amino group occurs easily at room temperature and gives 2,4-dihydroxyaniline.

Poison by subcutaneous and intraperitoneal routes. Human mutation data reported. When heated to decomposition it emits acrid smoke and irritating fumes.

Crystallise the triol from Et2O or Et2O/EtOH, and dry it in a vacuum. The picrate forms orange-red needles m 96o. [Beilstein 6 H 1087, 6 I 541, 6 II 1071, 6 III 6276.]