1,3-Cyclopentanedione

• Formula: C₅H₆O₂
• Molecular weight: 98.0999
• IUPAC Standard InChI: InChI=1S/C5H6O2/c6-4-1-2-5(7)3-4/h1-3H2 Copy

  
• IUPAC Standard InChIKey: LOGSONSNCYTHPS-UHFFFAOYSA-N Copy
• CAS Registry Number: 3859-41-4
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Other names: 1,3-Cyclopentadione; cyclopentane-1,3-dione
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• Information on this page:
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Mass spectrum (electron ionization)
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Phase change data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director

Reaction thermochemistry data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: John E. Bartmess

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

C₅H₅O₂^- +  =

By formula: C₅H₅O₂^- + H⁺ = C₅H₆O₂

Gas phase ion energetics data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

Ionization energy determinations

De-protonation reactions

C₅H₅O₂^- +  =

By formula: C₅H₅O₂^- + H⁺ = C₅H₆O₂

References

Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Wolfrom and Bobbitt, 1956
Wolfrom, M.L.; Bobbitt, J.M., Periodate Oxidation of Cyclic 1,3-Diketones, J. Am. Chem. Soc., 1956, 78, 2489-93. [all data]

Mishima, Matsuoka, et al., 2004
Mishima, M.; Matsuoka, M.; Lei, Y.X.; Rappoport, Z., Gas-phase acidities of disubstituted methanes and of enols of carboxamides substituted by electron-withdrawing groups, J. Org. Chem., 2004, 69, 18, 5947-5965, https://doi.org/10.1021/jo040196b . [all data]

Houk, Davis, et al., 1973
Houk, K.N.; Davis, L.P.; Newkome, G.R.; Duke, R.E., Jr.; Nauman, R.V., Photoelectron spectroscopy of cyclic β-diketones their enolone tautomers, J. Am. Chem. Soc., 1973, 95, 8364. [all data]

Gleiter, Hofmann, et al., 1980
Gleiter, R.; Hofmann, P.; Schang, P.; Sieber, A., The orbital sequence in cyclic 1,3-diketones, Tetrahedron, 1980, 36, 655. [all data]

Notes

Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  Tfus	Fusion (melting) point
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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