Aconitic acid

{{Chembox | Verifiedfields = changed | Watchedfields = changed | verifiedrevid = 477240926 | Name = Aconitic acid | ImageFile1 = Aconitic acid.svg | ImageClass1 = skin-invert | ImageSize1 = | ImageCaption1 = ''cis''-aconitic acid | ImageFile2 = (E)-aconitic acid.svg | ImageClass2 = skin-invert | ImageSize2 = | ImageCaption2 = ''trans''-aconitic acid | PIN = Prop-1-ene-1,2,3-tricarboxylic acid | OtherNames = Achilleic acid; equisetic acid; citridinic acid; pyrocitric acid; achilleaic acid; acinitic acid | Reference = <ref>{{ cite web | url = https://pubchem.ncbi.nlm.nih.gov/compound/309 | title = Aconitic Acid - Compound Summary (CID 309) | publisher = PubChem }}</ref> |Section1={{Chembox Identifiers | InChI = 1/C6H6O6/c7-4(8)1-3(6(11)12)2-5(9)10/h1H,2H2,(H,7,8)(H,9,10)(H,11,12) | StdInChI_Ref = {{stdinchicite|correct|chemspider}} | StdInChI = 1S/C4H8/c1-3-4-2/h3-4H,1-2H3 | InChIKey = GTZCVFVGUGFEME-UHFFFAOYAL | StdInChIKey_Ref = {{stdinchicite|correct|chemspider}} | StdInChIKey = GTZCVFVGUGFEME-UHFFFAOYSA-N | PubChem1 = 309 | PubChem1_Comment = (''cis'' and ''trans'') | ChemSpiderID1_Ref = {{chemspidercite|changed|chemspider}} | ChemSpiderID1 = 303 | ChemSpiderID1_Comment = (''cis'') | SMILES1 = | SMILES1_Comment = (''cis'') | InChI1 = | InChI1_Comment = (''cis'') | InChIKey1 = | InChI3 = | InChI3_Comment = (''cis'') | InChIKey3 = | PubChem2 = | PubChem2_Comment = (''trans'') | ChemSpiderID2_Ref = {{chemspidercite|changed|chemspider}} | ChemSpiderID2 = | ChemSpiderID2_Comment = (''trans'') | SMILES2 = | SMILES2_Comment = (''trans'') | InChI2 = | InChI2_Comment = (''trans'') | InChIKey2 = | InChI4 = | InChI4_Comment = (''trans'') | InChIKey4 = | ChEBI_Ref = {{ebicite|correct|EBI}} | ChEBI = | UNII_Ref = {{fdacite|correct|FDA}} | UNII = 93371T1BXP | UNII1_Ref = {{fdacite|correct|FDA}} | UNII1 = OF5471ZHRR | UNII1_Comment = (''cis'') | UNII2 = 7DB37960CW | UNII2_Ref = {{fdacite|correct|FDA}} | UNII2_Comment = (''trans'') | SMILES = | CASNo = 499-12-7 | CASNo_Ref = {{cascite|correct|CAS}} | CASNo1 = 585-84-2 | CASNo1_Comment = (''cis'') | CASNo1_Ref = {{cascite|correct|CAS}} | CASNo2 = 4023-65-8 | CASNo2_Comment = (''trans'') | CASNo2_Ref = {{cascite|correct|CAS}} | EC_number = | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | ChemSpiderID = | RTECS = }} |Section2={{Chembox Properties | C=6 | H=6 | O=6 | Appearance = Colorless crystals | Density = | MeltingPtC = 190 | MeltingPt_notes = (decomposes) (mixed isomers), 173 °C (''cis and trans isomers'') | BoilingPt = | pKa = 2.80, 4.46 (''trans isomer'')<ref>{{ cite book |author1=Dawson, R. M. C. |author2=Elliott, D. C. |author3=Elliott, W. H. | title = Data for Biochemical Research | edition = 3rd | location = Oxford | publisher = Clarendon Press | year = 1989 | isbn = 9780198552994 }}</ref> 2.78, 4.41, 6.21 (''cis isomer'')<ref>{{ cite journal |author1=Pfendt, L. |author2=Dražić, B. |author3= Popović, G. |author4=Drakulić, B. |author5=Vitnik, Ž |author6=Juranić, I. |title=Determination of all p''K''_a values of some di- and tri-carboxylic unsaturated and epoxy acids and their polylinear correlation with the carboxylic group atomic charges |journal=Journal of Chemical Research |year=2003 |volume=2003 |issue=5 |pages=247–248 |doi=10.3184/030823403103173732}}</ref> }} |Section3={{Chembox Hazards | MainHazards = | FlashPt = | AutoignitionPt = }} }}

'''Aconitic acid''' refers to organic compounds with the formula {{chem2|HO2CCH2C(CO2H)\dCHCO2H}}. A white solid, it is classified as a tricarboxylic acid. The two isomers are ''cis''-aconitic acid and ''trans''-aconitic acid. The conjugate base of ''cis''-aconitic acid, ''cis''-'''aconitate''' is an intermediate in the isomerization of citrate to isocitrate in the citric acid cycle. It is acted upon by the enzyme aconitase.

Aconitic acid can be synthesized by dehydration of citric acid using sulfuric acid:<ref>{{cite journal| author = Bruce, W. F. | title = Aconitic Acid | journal = Organic Syntheses | year = 1937 | volume = 17 | pages = 1|doi=10.15227/orgsyn.017.0001 }}</ref> :(HO₂CCH₂)₂C(OH)CO₂H → HO₂CCH=C(CO₂H)CH₂CO₂H + H₂O A mixture of isomers is generated in this way.

Aconitic acid was originally isolated from ''Aconitum napellus'' by Swiss chemist and apothecary Jacques Peschier in 1820.<ref>{{cite book |last1=Brande |first1=William Thomas |title=A Manual of Chemistry |volume=II |date=1848 |publisher=John W. Parker. |location=London |page=1344 |edition=6th |url=https://books.google.com/books?id=yyKxJYbsZgQC&dq=%22aconitic+acid%22&pg=PA1344 |access-date=8 November 2023}}</ref><ref>{{cite book |last1=Reichenbach |first1=Karl-Rudolf |title=Jacques Peschier (1769–1832): Ein Genfer Apotheker und Chemiker |date=2001 |publisher=Wissenschaftliche Verlagsgesellschaft mbH Stuttgart |location=Zürich |isbn=3804719090 |url=https://wellcomecollection.org/works/vjxjm7jj |access-date=8 November 2023}}</ref> It was first prepared by thermal dehydration.<ref>{{ cite journal | author = Pawolleck, B. | title = Substitutionsproducte der Citronensäure und ein Versuch zur Synthese der letzteren |trans-title=Substitution products of citric acid and an attempt at the synthesis of the latter | journal = Justus Liebig's Annalen der Chemie | year = 1875 | volume = 178 | issue = 2–3 | pages = 150–170 | url = https://babel.hathitrust.org/cgi/pt?id=mdp.39015026321573;view=1up;seq=554 | doi = 10.1002/jlac.18751780203 }}</ref>

Like the conjugate bases of other polycarboxylic acid, acotinic acid forms a variety of coordination complexes. One example is the coordination polymer [Zn₃(C₆H₃O₆)₂(H₂O)₆]_''n''.<ref>{{cite journal |doi=10.1016/j.ica.2008.10.008 |title=Synthesis and characterization of a novel photoluminescent three-dimensional metal–organic framework |date=2009 |last1=Zhang |first1=Kou-Lin |last2=Zhou |first2=Fang |last3=Yuan |first3=Li-Min |last4=Diao |first4=Guo-Wang |last5=Ng |first5=Seik Weng |journal=Inorganica Chimica Acta |volume=362 |issue=7 |pages=2510–2514 }}</ref>

==References== {{reflist}}

{{Citric acid cycle}}

Category:Tricarboxylic acids Category:Enoic acids