Benzoquinone (C6H4O2) is a quinone with a single benzene ring. There are 2 (out of 3 hypothetical) benzoquinones: 1,4-Benzoquinone, the more common isomer, right image (also para-benzoquinone, p-benzoquinone, para-quinone, or just quinone) 1,2-Benzoquinone, the less-common isomer, left image (also ortho-benzoquinone, o-benzoquinone, ortho-quinone)
1,3-benzoquinone itself does not exist though derivatives are known and have various potential applications.
See also Arene substitution pattern
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