- Formula: C5H6O2
- Molecular weight: 98.0999
- IUPAC Standard InChI:
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- IUPAC Standard InChIKey: LOGSONSNCYTHPS-UHFFFAOYSA-N
- 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
- Other names: 1,3-Cyclopentadione; cyclopentane-1,3-dione
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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
|9.46 ± 0.05||PE||Houk, Davis, et al., 1973||LLK|
|9.53||PE||Gleiter, Hofmann, et al., 1980||Vertical value; LLK|
C5H5O2- + =
By formula: C5H5O2- + H+ = C5H6O2
|rH°||1395. ± 8.8||kJ/mol||G+TS||Mishima, Matsuoka, et al., 2004||gas phase; Calc: keto form of acid more stable.; B|
|rG°||1366. ± 8.4||kJ/mol||IMRE||Mishima, Matsuoka, et al., 2004||gas phase; Calc: keto form of acid more stable.; B|
Go To: Top, Gas phase ion energetics data, Notes
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 «beta»-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]
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]
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
rG° Free energy of reaction at standard conditions rH° Enthalpy of reaction at standard conditions
- Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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