:Ethylenetetracarboxylic acid

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| verifiedrevid = 421502900

| ImageFile = Ethylenetetracarboxylic acid.svg

| ImageSize = 180

| ImageAlt = Structural formula

| ImageFile1 = Ethylenetetracarboxylic-acid-3D-spacefill.png

| ImageSize1 = 150

| ImageAlt1 = Space-filling model

| IUPACName = Ethene-1,1,2,2-tetracarboxylic acid

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|Section1={{Chembox Identifiers

| CASNo_Ref = {{cascite|correct|CAS}}

| CASNo = 4363-44-4

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = MV8N94W7XP

| PubChem = 12651152

| SMILES = O=C(O)/C(C(O)=O)=C(C(O)=O)\C(O)=O

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID = 11636515

| InChI = 1/C6H4O8/c7-3(8)1(4(9)10)2(5(11)12)6(13)14/h(H,7,8)(H,9,10)(H,11,12)(H,13,14)

| InChIKey = AIJZIRPGCQPZSL-UHFFFAOYAE

| StdInChI_Ref = {{stdinchicite|changed|chemspider}}

| StdInChI = 1S/C6H4O8/c7-3(8)1(4(9)10)2(5(11)12)6(13)14/h(H,7,8)(H,9,10)(H,11,12)(H,13,14)

| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}

| StdInChIKey = AIJZIRPGCQPZSL-UHFFFAOYSA-N

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|Section2={{Chembox Properties

| C=6 | H=4 | O=8

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|Section3={{Chembox Hazards

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Ethylenetetracarboxylic acid is an organic compound with formula {{chem|C|6|H|4|O|8}}, or (HO(OC)-)₂C=C(-(CO)OH)₂.

By removal of four protons, the acid yields the anion {{chem|C|6|O|8|4-}}, ethylenetetracarboxylate, which is one of the oxocarbon anions (consisting solely of oxygen and carbon). By loss of 1 through 3 protons, it forms the anions {{chem|C|6|H|3|O|8|-}}, {{chem|C|6|H|2|O|8|2-}}, and {{chem|C|6|HO|8|3-}}, called respectively trihydrogen-, dihydrogen-, and hydrogenethylenetetracarboxylate. The same names are used for the corresponding esters.

The acid can be obtained by hydrolysis of tetraethyl ethylenetetracarboxylate, which in turn can be obtained from diethyl dibromomalonate with sodium iodide.B. I. Zapadinskii, B. I. Liogon'kii, and A. A. Berlin (1973), Syntheses of Tetracarboxylic Acids. Russian Chemical Reviews, volume 42 issue 11, page 939. [http://www.iop.org/EJ/article/0036-021X/42/11/R04/RCR_42_11_R04.pdf Online version] accessed on 2010-01-03.

Ethylenetetracarboxylic dianhydride, a twofold acid anhydride of this compound, can be formed by direct dehydration at high temperature.John M. Patterson, Nabeel F. Haidar, Loren L. Braun and Walter T. Smith, Jr. (1981), The pyrolytic behavior of ethylenetetracarboxylic acid. Journal of Analytical and Applied Pyrolysis, Volume 2, Issue 4, Pages 331-337 {{doi|10.1016/0165-2370(81)80005-8}}