Hydroxyquinone
Hydroxyquinone often refers to a hydroxybenzoquinone, any organic compound with formula C
6H
4O
3 which can be viewed as a derivative of a benzoquinone through replacement of one hydrogen atom (H) by a hydroxyl group (-OH). When unqualified, the terms usually mean specifically the compound 2-hydroxy-1,4-benzoquinone, derived from 1,4-benzoquinone. That parent is sometimes simply called quinone, and this is the only hydroxy derivative of it.
![](../I/2-hydroxy-1%252C4-benzoquinone.svg.png.webp)
1,4-benzoquinone
(Hydroxyquinone)
More generally, the term may refer to any derivative of any quinone (such as 1,2-benzoquinone, 1,4-naphthoquinone or 9,10-anthraquinone), where any number n of hydrogens have been replaced by n hydroxyls. In this case the number n is indicated by a multiplier prefix (mono-, di-, tri-, etc.), and the parent quinone's name is used instead of just "quinone" — as in tetrahydroxy-1,4-benzoquinone.
- Tetrahydroxy-
1,4-benzoquinone - 5-Hydroxy-
1,4-naphthoquinone
(Juglone) - 1,2-Dihydroxy-
9,10-anthraquinone
(Alizarin)
The hydroxyquinones (in the particular or the general sense) include many biologically and industrially important compounds, and are a building block of many medicinal drugs.
Hydroxyquinones with hydroxyls adjacent to the ketone groups often exhibit intramolecular hydrogen bonding, which affects their redox properties and their biochemical properties.[1]
The term "hydroxyquinone" should not be confused with hydroquinone, the common name of benzene-1,4-diol.
References
- J. Khalafy and J.M. Bruce (2002), Oxidative dehydrogenation of 1-tetralones: Synthesis of juglone, naphthazarin, and [alpha]-hydroxyanthraquinones. Journal of Sciences, Islamic Republic of Iran, volume 13 issue 2, pages 131-139.