Girish Mahajan (Editor)

1,2 Benzoquinone

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Formula  C6H4O2
Density  1.26 g/cm³
Molar mass  108.0964 g/mol
Boiling point  213.3 °C
1,2-Benzoquinone httpsuploadwikimediaorgwikipediacommonsthu

Related compounds  1,4-benzoquinonequinone

1,2-Benzoquinone, also called ortho-benzoquinone, is an organic compound with formula | C=6 | H=4 | O=2 . It is one of the two isomers of quinone, the other being 1,4-benzoquinone. It is a red volatile solid that is soluble in water and ethyl ether. It is rarely encountered because of its instability, but it is of fundamental interest as the parent ortho-quinone, of which many analogues are known.



The molecule has C2v symmetry. X-ray crystallography shows that the double bonds are localized, with alternatingly long and short C-C distances within the ring. The C=O distances of 1.21 Å are characteristic of ketones.

Preparation and occurrence

1,2-Benzoquinone is produced on oxidation of catechol exposed to air in aqueous solution or by ortho oxidation of a phenol. It is a precursor to melanin.

A strain of the bacterium Pseudomonas mendocina metabolises benzoic acid, yielding 1,2-benzoquinone via catechol.


1,2-Benzoquinone Wikipedia