In chemistry, 1,4-benzoquinonetetracarboxylic acid is an organic compound with formula C
10H
4O
10, or (C6O2)(-(CO)OH)4, which can be viewed as deriving from para-benzoquinone C
6H
4O
2 through replacement of the four hydrogen atoms by carboxyl functional groups -(CO)OH.
By removal of four protons, the acid is expected to yield the anion C
10O4−
10, benzoquinonetetracarboxylate, which is one of the oxocarbon anions (consisting solely of oxygen and carbon). By loss of 1 through 3 protons, it forms the anions C
10H
3O−
10, C
10H
2O2−
10, and C
10HO3−
10, called respectively trihydrogen-, dihydrogen-, and hydrogenbenzoquinonetetracarboxylate. The same names are used for the corresponding esters.
Removal of two water molecules gives the compound benzoquinonetetracarboxylic dianhydride, C
10O
8, one of the oxides of carbon.[1]
The acid can be obtained by from durene (1,2,4,5-tetramethylbenzene) via dinitropyromellitic and diaminopyromellitic acids.[2][3][4]