1,3-Cyclopentanedione

1,3-Cyclopentanedione
Names
	Preferred IUPAC name Cyclopentane-1,3-dione
Identifiers
CAS Number	3859-41-4;
3D model (JSmol)	Interactive image;
Beilstein Reference	1362728
ChEBI	CHEBI:41456;
ChEMBL	ChEMBL224233;
ChemSpider	69875;
ECHA InfoCard	100.021.249
EC Number	223-372-8;
Gmelin Reference	200797
PubChem CID	77466;
UNII	98107S5K06;
CompTox Dashboard (EPA)	DTXSID90191911 ;
	InChI InChI=1S/C5H6O2/c6-4-1-2-5(7)3-4/h1-3H2 Key: LOGSONSNCYTHPS-UHFFFAOYSA-N;
	SMILES C1CC(=O)CC1=O;
Properties
Appearance	white solid
Density	1.37 g/cm3
Melting point	149–151 °C (300–304 °F; 422–424 K)
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H315, H319, H335
Precautionary statements	P261, P264, P271, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P403+P233, P405, P501
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

1,3-Cyclopentanedione is an organic compound with the formula (CH₂)₃(CO)₂. It is one of two isomeric cyclopentanediones, the other being 1,2-cyclopentanedione. The enol is predicted to be about 1-3 kcal/mol more stable than the diketo form.^[1] The enol structure has been confirmed by X-ray crystallography.^[2]

Preparation

The compound is prepared by hydrogenation of 2-cyclopentene-1,4-dione using zinc/acetic acid.^[3]^[4]

References

^ Jana, Kalyanashis; Ganguly, Bishwajit (2018). "DFT Study to Explore the Importance of Ring Size and Effect of Solvents on the Keto–Enol Tautomerization Process of α- and β-Cyclodiones". ACS Omega. 3 (7): 8429–8439. doi:10.1021/acsomega.8b01008. PMC 6644555. PMID 31458971.
^ Katrusiak, A. (1990). "Structure of 1,3-cyclopentanedione". Acta Crystallographica Section C: Crystal Structure Communications. 46 (7): 1289–1293. Bibcode:1990AcCrC..46.1289K. doi:10.1107/S0108270189011352.
^ McIntosh, John M.; Beaumier, Pierre. (1972). "Improved Preparation of 1,3-cyclopentanedione". The Journal of Organic Chemistry. 37 (18): 2905–2906. doi:10.1021/jo00983a027.
^ Gary H. Rasmusson; Herbert O. House; Edward F. Zaweski; Charles H. DePuy (1962). "2-Cyclopentene-1,4-Dione". Organic Syntheses. 42: 36. doi:10.15227/orgsyn.042.0036.

[1] Jana, Kalyanashis; Ganguly, Bishwajit (2018). "DFT Study to Explore the Importance of Ring Size and Effect of Solvents on the Keto–Enol Tautomerization Process of α- and β-Cyclodiones". ACS Omega. 3 (7): 8429–8439. doi:10.1021/acsomega.8b01008. PMC 6644555. PMID 31458971.

[2] Katrusiak, A. (1990). "Structure of 1,3-cyclopentanedione". Acta Crystallographica Section C: Crystal Structure Communications. 46 (7): 1289–1293. Bibcode:1990AcCrC..46.1289K. doi:10.1107/S0108270189011352.

[3] McIntosh, John M.; Beaumier, Pierre. (1972). "Improved Preparation of 1,3-cyclopentanedione". The Journal of Organic Chemistry. 37 (18): 2905–2906. doi:10.1021/jo00983a027.

[4] Gary H. Rasmusson; Herbert O. House; Edward F. Zaweski; Charles H. DePuy (1962). "2-Cyclopentene-1,4-Dione". Organic Syntheses. 42: 36. doi:10.15227/orgsyn.042.0036.

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