1,3-Cyclohexanedione, 5,5-dimethyl-
- Formula: C8H12O2
- Molecular weight: 140.1797
- IUPAC Standard InChI: InChI=1S/C8H12O2/c1-8(2)4-6(9)3-7(10)5-8/h3-5H2,1-2H3
- IUPAC Standard InChIKey: BADXJIPKFRBFOT-UHFFFAOYSA-N
- CAS Registry Number: 126-81-8
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript. - Other names: Cyclomethone; Dimedon; Dimedone; Lu 274; Medon; Methon; Methone; 1,1-Dimethyl-3,5-cyclohexanedione; 1,1-Dimethyl-3,5-diketocyclohexane; 5,5-Dimethyl-1,3-cyclohexanedione; 5,5-Dimethyldihydroresorcinol; 5,5-Dimethylhydroresorcinol; 5,5-Dimethylcyclohexane-1,3-dione; 5,5-Dimethyl-1,3-cyclohexadione; 5,5-Dimethyl-1,3-dihydroresorcinol; NSC 14984
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Gas phase 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°gas | -91.68 ± 0.45 | kcal/mol | Ccb | Pilcher, Parchment, et al., 1993 |
Condensed phase 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°solid | -115.5 ± 0.38 | kcal/mol | Ccb | Pilcher, Parchment, et al., 1993 | |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°solid | -1046.8 ± 0.29 | kcal/mol | Ccb | Pilcher, Parchment, et al., 1993 | Corresponding ΔfHºsolid = -115.5 kcal/mol (simple calculation by NIST; no Washburn corrections) |
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 as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| Tfus | 421.4 | K | N/A | Wolfrom and Bobbitt, 1956 | Uncertainty assigned by TRC = 3. K; TRC |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔsubH° | 23.9 ± 0.26 | kcal/mol | V | Pilcher, Parchment, et al., 1993 | ALS |
| ΔsubH° | 23.9 ± 0.26 | kcal/mol | ME | Pilcher, Parchment, et al., 1993 | AC |
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
C8H11O2- + =
By formula: C8H11O2- + H+ = C8H12O2
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 338.8 ± 2.1 | kcal/mol | G+TS | Cumming and Kebarle, 1978 | gas phase; Acid: dimedone |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 331.1 ± 2.0 | kcal/mol | IMRE | Cumming and Kebarle, 1978 | gas phase; Acid: dimedone |
Gas Chromatography
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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: NIST Mass Spectrometry Data Center, William E. Wallace, director
Normal alkane RI, non-polar column, temperature ramp
| Column type | Active phase | I | Reference | Comment |
|---|---|---|---|---|
| Capillary | Ultra-1 | 1101. | Okumura, 1991 | 25. m/0.32 mm/0.25 μm, He, 3. K/min; Tstart: 80. C; Tend: 260. C |
Normal alkane RI, non-polar column, custom temperature program
| Column type | Active phase | I | Reference | Comment |
|---|---|---|---|---|
| Capillary | HP-5 | 1176. | Ventanas, Estevez, et al., 2008 | 50. m/0.32 mm/1.05 μm, Helium; Program: 40 0C (10 min) 5 0C/min -> 200 0C 15 0C/min -> 250 0C (10 min) |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas Chromatography, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Pilcher, Parchment, et al., 1993
Pilcher, G.; Parchment, O.G.; Hillier, I.H.; Heatley, F.; Fletcher, D.; Ribeiro da Silva, M.A.V.; Ferrao, M.L.C.C.H.; Monte, J.S.; Jiye, F.,
Thermochemical and theoretical studies on cyclohexanediones,
J. Phys. Chem., 1993, 97, 243-247. [all data]
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]
Cumming and Kebarle, 1978
Cumming, J.B.; Kebarle, P.,
Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A),
Can. J. Chem., 1978, 56, 1. [all data]
Okumura, 1991
Okumura, T.,
retention indices of environmental chemicals on methyl silicone capillary column,
Journal of Environmental Chemistry (Japan), 1991, 1, 2, 333-358, https://doi.org/10.5985/jec.1.333
. [all data]
Ventanas, Estevez, et al., 2008
Ventanas, S.; Estevez, M.; Andres, A.I.; Ruiz, J.,
Analysis of volatile compounds of Iberian dry-cured loins with different intramuscular fat contents using SPME-DED,
Meat Sci., 2008, 79, 1, 172-180, https://doi.org/10.1016/j.meatsci.2007.08.011
. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas Chromatography, References
- Symbols used in this document:
Tfus Fusion (melting) point ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°solid Enthalpy of formation of solid at standard conditions ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔsubH° Enthalpy of sublimation at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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