1,2-Benzoquinone, also called ortho-benzoquinone or cyclohexa-3,5-diene-1,2-dione, is a ketone

Ketone

In organic chemistry, a ketone is an organic compound with the structure RCR', where R and R' can be a variety of atoms and groups of atoms. It features a carbonyl group bonded to two other carbon atoms. Many ketones are known and many are of great importance in industry and in biology...

, with formula C₆H₄O₂. It is one of the two isomers of quinone

Quinone

A quinone is a class of organic compounds that are formally "derived from aromatic compounds [such as benzene or naphthalene] by conversion of an even number of –CH= groups into –C– groups with any necessary rearrangement of double bonds," resulting in "a fully conjugated cyclic dione structure."...

, the other being 1,4-benzoquinone

1,4-Benzoquinone

1,4-Benzoquinone, commonly known as para-quinone, is a chemical compound with the formula C6H4O2. In a pure state, it forms bright-yellow crystals with a characteristic irritating odor, resembling that of chlorine, bleach, and hot plastic. Impure samples are often dark-colored due to the presence...

.

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

Phenol

Phenol, also known as carbolic acid, phenic acid, is an organic compound with the chemical formula C6H5OH. It is a white crystalline solid. The molecule consists of a phenyl , bonded to a hydroxyl group. It is produced on a large scale as a precursor to many materials and useful compounds...

.
It is a precursor to melanin

Melanin

Melanin is a pigment that is ubiquitous in nature, being found in most organisms . In animals melanin pigments are derivatives of the amino acid tyrosine. The most common form of biological melanin is eumelanin, a brown-black polymer of dihydroxyindole carboxylic acids, and their reduced forms...

.
It is a red substance soluble in water and insoluble in ethyl ether.

A strain of the bacterium Pseudomonas mendocina

Pseudomonas mendocina

Pseudomonas mendocina is a Gram-negative environmental bacterium that can cause opportunistic nosocomial infections, such as infective endocarditis and spondylodiscitis, although cases are very rare. It has potential use in bioremediation as it is able to degrade toluene. Based on 16S rRNA...

 metabolyzes

Metabolism

Metabolism is the set of chemical reactions that happen in the cells of living organisms to sustain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. Metabolism is usually divided into two categories...

 benzoic acid

Benzoic acid

Benzoic acid , C7H6O2 , is a colorless crystalline solid and the simplest aromatic carboxylic acid. The name derived from gum benzoin, which was for a long time the only source for benzoic acid. Its salts are used as a food preservative and benzoic acid is an important precursor for the synthesis...

 yielding 1,2-benzoquinone (via cathecol) as the final product.

See also

• 1,4-Benzoquinone
  1,4-Benzoquinone
  1,4-Benzoquinone, commonly known as para-quinone, is a chemical compound with the formula C6H4O2. In a pure state, it forms bright-yellow crystals with a characteristic irritating odor, resembling that of chlorine, bleach, and hot plastic. Impure samples are often dark-colored due to the presence...
  
  
• Tetrabromo-1,2-benzoquinone (o-bromanil)
• Tetrachloro-1,2-benzoquinone (o-chloranil)
• Tetrahydroxy-1,2-benzoquinone
• Hydroxybenzoquinone
  Hydroxybenzoquinone
  A hydroxybenzoquinone is any of several organic compounds with formula , which can be viewed as derivatives of a benzoquinone through replacement of one hydrogen atom by an hydroxyl group ....