dimedone
{{chembox
| Watchedfields = changed
| verifiedrevid = 401997177
| ImageFileL1 =dimedone.png
| ImageFileR1 =Dimedone-3D-balls.png
| PIN =5,5-Dimethylcyclohexane-1,3-dione
| OtherNames =Cyclomethone,
5,5-dimethyl-1,3-cyclohexanedione,
Dimethyldihydroresorcinol,
Methone
|Section1={{Chembox Identifiers
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 29091
| InChI = 1/C8H12O2/c1-8(2)4-6(9)3-7(10)5-8/h3-5H2,1-2H3
| InChIKey = BADXJIPKFRBFOT-UHFFFAOYAX
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/C8H12O2/c1-8(2)4-6(9)3-7(10)5-8/h3-5H2,1-2H3
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = BADXJIPKFRBFOT-UHFFFAOYSA-N
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo =126-81-8
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = B2B5DSX2FC
| PubChem =31358
| SMILES = O=C1CC(=O)CC(C)(C)C1
}}
|Section2={{Chembox Properties
| C=8|H=12|O=2
| MolarMass =
| Appearance =White solid
| Density =
| MeltingPtC = 147 to 150
| MeltingPt_notes = (decomposes)
| BoilingPt =
| Solubility =
}}
|Section3={{Chembox Hazards
| MainHazards =
| FlashPt =
| AutoignitionPt =
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Dimedone is an organic compound with the formula {{chem2|(CH3)2C(CH2)2(CO)2(CH2)}}. Classified as a cyclic diketone, it is a derivative of 1,3-cyclohexanedione. It is a white solid that is soluble in water, as well as ethanol and methanol. It once was used as a reagent to test for the aldehyde functional group.
Synthesis
Dimedone is prepared from mesityl oxide and diethyl malonate via a Michael addition reaction.{{ cite journal | journal = Organic Syntheses | volume = 15 | year = 1935 | pages = 16 | url = http://www.orgsyn.org/orgsyn/prep.asp?prep=cv2p0200 | title = 5,5-dimethyl-1,3-cyclohexanedione | author = R. L. Shriner and H. R. Todd | doi=10.1002/0471264180.os015.06| isbn = 0471264229 | url-access = subscription }}{{cite web |title=Dimedone synthesis |url=https://www.chemtube3d.com/conjugate-addition-dimedone-synthesis/ |website=ChemTube3D |access-date=11 May 2023 |language=en}}
Chemical properties
= Tautomerism =
Dimedone is in equilibrium with its tautomer in solution — in a 2:1 keto to enol ratio in chloroform.{{Clayden|pages=530}}
Image:Dimedone-tautomerism-2D-skeletal.png
Crystalline dimedone contains chains of molecules, in the enol form, linked by hydrogen bonds:{{ cite journal | journal = Acta Crystallogr. C | volume = 53 | issue = 10 |date=October 1997 | pages = IUC9700013 | doi = 10.1107/S0108270197099423 | title = Dimedone at 133K | author = M. Bolte and M. Scholtyssik | doi-access = free | bibcode = 1997AcCrC..53C0013B }}
= Reaction with aldehydes =
Dimedone reacts with aldehydes to give crystalline derivatives, whose melting points can be used to distinguish between aldehydes.{{Cite journal |last1=Horning |first1=E. C. |last2=Horning |first2=M. G. |title=Methone Derivatives of Aldehydes |date=1946 |url=https://pubs.acs.org/doi/abs/10.1021/jo01171a014 |journal=The Journal of Organic Chemistry |language=en |volume=11 |issue=1 |pages=95–99 |doi=10.1021/jo01171a014 |pmid=21013441 |issn=0022-3263|url-access=subscription }}