{{chembox | Verifiedfields = changed | Watchedfields = changed | verifiedrevid = 477223479 | Reference=<ref>[http://www.sigmaaldrich.com/catalog/search/ProductDetail/ALDRICH/177229 4H-Pyran-4-one] at Sigma-Aldrich</ref> | ImageFile=4-Pyranone.png | ImageSize=80px | PIN=4''H''-Pyran-4-one | OtherNames=γ-Pyrone<br>4-Pyranone |Section1={{Chembox Identifiers | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | ChemSpiderID = 7680 | InChI = 1/C5H4O2/c6-5-1-3-7-4-2-5/h1-4H | InChIKey = CVQUWLDCFXOXEN-UHFFFAOYAG | SMILES1 = O=C\1/C=C\O/C=C/1 | StdInChI_Ref = {{stdinchicite|correct|chemspider}} | StdInChI = 1S/C5H4O2/c6-5-1-3-7-4-2-5/h1-4H | StdInChIKey_Ref = {{stdinchicite|correct|chemspider}} | StdInChIKey = CVQUWLDCFXOXEN-UHFFFAOYSA-N | CASNo_Ref = {{cascite|correct|CAS}} | CASNo=108-97-4 | UNII_Ref = {{fdacite|correct|FDA}} | UNII = UJ7X07IM7Z | PubChem=7968 | ChEBI_Ref = {{ebicite|correct|EBI}} | ChEBI = 37966 | SMILES=C1=COC=CC1=O }} |Section2={{Chembox Properties | Formula=C<sub>5</sub>H<sub>4</sub>O<sub>2</sub> | MolarMass=96.08 | MeltingPtC = 32 to 34 | BoilingPtC = 210 to 215 }} |Section3={{Chembox Hazards | MainHazards= | FlashPtC =101 }} }}
'''4-Pyrone''' ('''γ-pyrone''' or '''pyran-4-one''') is an unsaturated cyclic chemical compound with the molecular formula C<sub>5</sub>H<sub>4</sub>O<sub>2</sub>.It is isomeric with 2-pyrone.
==Preparation== 4-Pyrone is prepared via the thermal decarboxylation of chelidonic acid.<ref name=Weygand>{{cite book|last1=Weygand|first1=Conrad|editor1-last=Hilgetag|editor1-first=G.|editor2-last=Martini|editor2-first=A.|title=Weygand/Hilgetag Preparative Organic Chemistry|date=1972|publisher=John Wiley & Sons, Inc.|location=New York|isbn=0471937495|pages=533–534, & 1009|edition=4th}}</ref>
==Reactions== 4-Pyrone and its derivatives react with amines in protic solvents to form 4-Pyridones.<ref name=Weygand /><ref>{{cite journal|last1=Van Allan|first1=J. A.|last2=Reynolds|first2=G. A.|last3=Alessi|first3=J. T.|last4=Chie Chang|first4=S.|last5=C. Joines|first5=R.|title=Reactions of 4-pyrones with primary amines. A new class of ionic associates|journal=Journal of Heterocyclic Chemistry|date=1971|volume=8|issue=6|pages=919–922|doi=10.1002/jhet.5570080606}}</ref><ref>{{cite journal|last1=Cook|first1=Denys|title=The Preparation, Properties, and Structure of 2,6-bis-(Alkyamino)-2,5-heptadien-4-ones|journal=Canadian Journal of Chemistry|date=1963|volume=41|issue=6|pages=1435–1440|doi=10.1139/v63-195|doi-access=}}</ref>
==Derivatives== 4-Pyrone forms the central core of several natural chemical compounds,<ref>{{cite journal |doi=10.1016/j.bmc.2008.11.001|title=Γ-Pyrone natural products—A privileged compound class provided by nature |year=2009 |last1=Wilk |first1=Wolfram |last2=Waldmann |first2=Herbert |last3=Kaiser |first3=Markus |journal=Bioorganic & Medicinal Chemistry |volume=17 |issue=6 |pages=2304–2309 |pmid=19042133}}</ref> including maltol, meconic acid, kojic acid, and of the important class of the flavones.
:{| class="wikitable" |70px |120px |- | Maltol | Kojic acid |}
==See also== * Pyrone * 4-Pyridone * Dehydroacetic acid
==References== <references/>
{{DEFAULTSORT:Pyrone, 4-}} Category:4-Pyrones