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IUPAC name Cyclohexa-2,5-diene-1,4-dione
Other names p-benzoquinone; p-quinone
CAS number 106-51-4
RTECS number DK2625000
Molecular formula C6H4O2
Molar mass 108.095 g/mol
Appearance Yellow solid
Density 1.318 g/cm3 at 20 °C, solid
Melting point

115 °C

Boiling point


Solubility in water Slightly soluble
Solubility Slightly soluble in pteroleum ether; soluble in acetone; very soluble in ethanol, benzene, diethyl ether
Main hazards Toxic
R-phrases R23/25 R36/37/38 R50
S-phrases S26 S28 S45 S61
Related Compounds
Related compounds 1,2-Benzoquinone
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

1,4-Benzoquinone is the chemical compound with the formula C6H4O2. This nonaromatic six-membered ring compound is the oxidized derivative of 1,4-hydroquinone.[1] The molecule is multifunctional: it exhibits properties of a ketone, forming an oxime; an oxidant, forming the dihydroxy derivative; and an alkene, undergoing addition reactions.


Applications in organic synthesis

It is used as a hydrogen acceptor and oxidant in organic synthesis.[2] 1,4-Benzoquinone serves as a dehydrogenation reagent. It is also uses as a dienophile in Diels Alder reactions.[3]

Related 1,4-benzoquinones

A variety of derivatives and analogues are known. Illustrative examples:

  • 1,4-Naphthoquinone, derived by oxidation of naphthalene with chromium trioxide.[4]
  • 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, a stronger oxidant and dehydrogenation agent than 1,4-benzoquinone.[5]
  • Ubiquinone-1, a naturally occurring 1,4-benzoquinone.
  • Chloro-p-benzoquinone, (CAS no. [695-99-8])[6]
  • Chloranil, 1,4-C6Cl4O2, a stronger oxidant and dehydrogenation agent than 1,4-benzoquinone.

See also


  1. ^ H. W. Underwood, Jr. and W. L. Walsh (1943). "Quinone". Org. Synth.; Coll. Vol. 2: 553. 
  2. ^ Yang, T.-K.; Shen, C.-Y. ”1,4-Benzoquinone” in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. doi:10.1002/047084289.
  3. ^ Oda, M.; Kawase, T.; Okada, T.; Enomoto, T. (1998). "2-Cyclohexene-1,4-dione". Org. Synth.; Coll. Vol. 9: 186. 
  4. ^ E. A. Braude E. A.; Fawcett, J. S. (1963). "1,4-Naphthoquinone". Org. Synth.; Coll. Vol. 4: 698. 
  5. ^ Vogel, E.; Klug, W.; Breuer, A. (1988). "1,6-Methano[10]annulene". Org. Synth.; Coll. Vol. 6: 731. 
  6. ^ Harman, R. E. (1963). "Chloro-p-benzoquinone". Org. Synth.; Coll. Vol. 4: 148. 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "1,4-Benzoquinone". A list of authors is available in Wikipedia.
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