Benzenehexol, also called hexahydroxybenzene, is an organic compound with formula or . It is a six-fold phenol of benzene. The product is also called hexaphenol, but this name has been used also for other substances.
Benzenehexol is a crystalline solid soluble in hot water, with a melting point above 310ð. It can be prepared from inositol (cyclohexanehexol). Oxidation of benzenehexol yields tetrahydroxy-p-benzoquinone (THBQ), rhodizonic acid, and dodecahydroxycyclohexane. Conversely, benzenehexol can be obtained by reduction of sodium THBQ salt with SnCl<sub>2</sub>/HCl.
Benzenehexol is a starting material for a class of discotic liquid crystals.
Benzenehexol forms an adduct with 2,2'-bipyridine, with 1:2 molecular ratio.
Like most phenols, benzenehexol can lose the six H<sup>+</sup> ions from the hydroxyl groups, yielding the hexaanion . The potassium salt of this anion is one of the components of Liebig's so-called "potassium carbonyl", the product of the reaction of carbon monoxide with potassium. The hexaanion is produced by trimerization of the acetylenediolate anion when heating potassium acetylenediolate . The nature of was clarified by Rudolf Nietzki and in 1885, who found that its hydrolysis yielded benzenehexol.
The lithium salt of this anion, Li<sub>6</sub>C<sub>6</sub>O<sub>6</sub> has been considered for electric battery applications.
Hexahydroxy benzene forms esters such as the hexaacetate (-O(CO)CH<sub>3</sub>)<sub>6</sub> (melting point 220 ðC) and ethers like hexa-tert-butoxybenzene (-OC(CH<sub>3</sub>)<sub>3</sub>)<sub>6</sub> (melting point 223 ðC).