1,3-Cyclohexadiene
- Formula: C6H8
- Molecular weight: 80.1277
- IUPAC Standard InChIKey: MGNZXYYWBUKAII-UHFFFAOYSA-N
- CAS Registry Number: 592-57-4
- 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: Cyclohexa-1,3-diene; 1,2-Dihydrobenzene
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Reaction thermochemistry data
Go To: Top, Gas phase ion energetics data, References, Notes
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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
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
C6H7- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1561. ± 17. | kJ/mol | G+TS | Lee and Squires, 1986 | gas phase; Between SiH4, tBuOH; value altered from reference due to change in acidity scale; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1531. ± 17. | kJ/mol | IMRB | Lee and Squires, 1986 | gas phase; Between SiH4, tBuOH; value altered from reference due to change in acidity scale; B |
By formula: 2H2 + C6H8 = C6H12
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -224.4 ± 1.2 | kJ/mol | Chyd | Turner, Mallon, et al., 1973 | liquid phase; solvent: Glacial acetic acid; ALS |
ΔrH° | -229.6 ± 0.42 | kJ/mol | Chyd | Kistiakowsky, Ruhoff, et al., 1936 | gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -231.7 ± 0.4 kJ/mol; At 355 °K; ALS |
By formula: C8H12 = C6H8 + C2H4
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 136. | kJ/mol | Kin | Huybrechts, Rigaux, et al., 1980 | gas phase; Diels-Alder addition at 560°K, see Van Mele, Boon, et al., 1986; ALS |
By formula: C6H8N2O = N2O + C6H8
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -3.5 ± 0.3 | kJ/mol | Kin | Oth, Olsen, et al., 1977 | liquid phase; solvent: THF; At 452 K; ALS |
By formula: C6H8 = C6H8
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -1.6 ± 0.8 | kJ/mol | Eqk | Taskinen and Nummelin, 1986 | liquid phase; solvent: (CH3)2SO; GLC; ALS |
By formula: C6H8 + O2 = C8H8O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -175. ± 20. | kJ/mol | Cpha | Olmsted, 1980 | liquid phase; solvent: CCl4; ALS |
By formula: C6H8 + C6N4 = C12H8N4
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -120.9 ± 3.2 | kJ/mol | Cm | Rogers, 1972 | liquid phase; ALS |
By formula: C12H8N4 = C6H8 + C6N4
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 120.9 ± 3.2 | kJ/mol | Cm | Rogers, 1972 | solid phase; ALS |
Gas phase ion energetics data
Go To: Top, Reaction thermochemistry data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
Data compiled as indicated in comments:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
View reactions leading to C6H8+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Proton affinity (review) | 837. | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 804.5 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.25 | PE | Kimura, Katsumata, et al., 1981 | LLK |
8.25 ± 0.02 | PE | Bieri, Burger, et al., 1977 | LLK |
8.25 ± 0.03 | PI | Demeo and El-Sayed, 1970 | RDSH |
8.25 | PE | Bischof and Heilbronner, 1970 | RDSH |
8.28 ± 0.05 | EI | Franklin and Carroll, 1969 | RDSH |
8.32 | PE | Worley, Webb, et al., 1979 | Vertical value; LLK |
8.25 ± 0.03 | PE | Heilbronner, Hoshi, et al., 1976 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C3H2+ | 23.51 ± 0.50 | ? | EI | Franklin and Carroll, 1969 | RDSH |
C3H3+ | 14.87 ± 0.10 | ? | EI | Franklin and Carroll, 1969 | RDSH |
C3H4+ | 14.52 ± 0.10 | ? | EI | Franklin and Carroll, 1969 | RDSH |
C4H2+ | 19.81 ± 0.10 | C2H2+2H2 | EI | Franklin and Carroll, 1969 | RDSH |
C4H3+ | 17.62 ± 0.10 | C2H2+H2+H? | EI | Franklin and Carroll, 1969 | RDSH |
C4H4+ | 13.91 ± 0.20 | C2H2+H2 | EI | Franklin and Carroll, 1969 | RDSH |
C4H5+ | 14.69 ± 0.10 | C2H2+H | EI | Franklin and Carroll, 1969 | RDSH |
C4H6+ | 12.60 ± 0.10 | C2H2 | EI | Franklin and Carroll, 1969 | RDSH |
C5H3+ | 15.44 ± 0.10 | CH3+H2? | EI | Franklin and Carroll, 1969 | RDSH |
C5H5+ | 13.02 ± 0.10 | CH3 | EI | Franklin and Carroll, 1969 | RDSH |
C6H5+ | 13.92 ± 0.10 | H2+H | EI | Franklin and Carroll, 1969 | RDSH |
C6H6+ | 10.12 ± 0.10 | H2 | EI | Franklin and Carroll, 1969 | RDSH |
C6H6+ | 9.88 ± 0.10 | H2 | EI | Franklin and Carroll, 1969 | RDSH |
C6H7+ | 10.45 | H | PIPECO | Lias and Ausloos, 1985 | LBLHLM |
C6H7+ | 10.82 ± 0.10 | H | EI | Franklin and Carroll, 1969 | RDSH |
De-protonation reactions
C6H7- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1561. ± 17. | kJ/mol | G+TS | Lee and Squires, 1986 | gas phase; Between SiH4, tBuOH; value altered from reference due to change in acidity scale; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1531. ± 17. | kJ/mol | IMRB | Lee and Squires, 1986 | gas phase; Between SiH4, tBuOH; value altered from reference due to change in acidity scale; B |
References
Go To: Top, 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.
Lee and Squires, 1986
Lee, R.E.; Squires, R.R.,
Anionic homoaromaticity: A gas phase experimental study,
J. Am. Chem. Soc., 1986, 105, 5078. [all data]
Turner, Mallon, et al., 1973
Turner, R.B.; Mallon, B.J.; Tichy, M.; Doering, W.v.E.; Roth, W.R.; Schroder, G.,
Heats of hydrogenation. X. Conjugative interaction in cyclic dienes and trienes,
J. Am. Chem. Soc., 1973, 95, 8605-8610. [all data]
Kistiakowsky, Ruhoff, et al., 1936
Kistiakowsky, G.B.; Ruhoff, J.R.; Smith, H.A.; Vaughan, W.E.,
Heats of organic reactions. IV. Hydrogenation of some dienes and of benzene,
J. Am. Chem. Soc., 1936, 58, 146-153. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]
Huybrechts, Rigaux, et al., 1980
Huybrechts, G.; Rigaux, D.; Vankeerberghen, J.; Van Mele, B.,
Kinetics of the Diels-Alder addition of ethene to cyclohexa-1,3-diene and its reverse reaction in the gas phase,
Int. J. Chem. Kinet., 1980, 12, 253-259. [all data]
Van Mele, Boon, et al., 1986
Van Mele, B.; Boon, G.; Huybrechts, G.,
Gas-phase kinetic and thermochemical data for endo- and exo-5-monosubstituted bicyclo[2.2.2]oct-2-enes,
Int. J. Chem. Kinet., 1986, 18, 537-545. [all data]
Oth, Olsen, et al., 1977
Oth, J.F.M.; Olsen, H.; Synder, J.P.,
Energetics of heteroextrusion reactions. N2 vs. N2O,
J. Am. Chem. Soc., 1977, 99, 8505-8507. [all data]
Taskinen and Nummelin, 1986
Taskinen, E.; Nummelin, K.,
Thermodynamics of vinyl ethers. 31. Isomer equilibria in some six- and seven-membered cyclic dienes,
J. Org. Chem., 1986, 50, 4844-4847. [all data]
Olmsted, 1980
Olmsted, J., III,
Photocalorimetric studies of singlet oxygen reactions,
J. Am. Chem. Soc., 1980, 102, 66-71. [all data]
Rogers, 1972
Rogers, F.E.,
Thermochemistry of the Diels-Alder reactions. II. Heat of addition of several dienes to tetracyanoethylene,
J. Phys. Chem., 1972, 76, 106-109. [all data]
Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G.,
Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update,
J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018
. [all data]
Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S.,
Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules
in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]
Bieri, Burger, et al., 1977
Bieri, G.; Burger, F.; Heilbronner, E.; Maier, J.P.,
Valence ionization enrgies of hydrocarbons,
Helv. Chim. Acta, 1977, 60, 2213. [all data]
Demeo and El-Sayed, 1970
Demeo, D.A.; El-Sayed, M.A.,
Ionization potential and structure of olefins,
J. Chem. Phys., 1970, 52, 2622. [all data]
Bischof and Heilbronner, 1970
Bischof, P.; Heilbronner, E.,
Photoelektron-Spektren von Cycloalkenen und Cycloalkadienen,
Helv. Chim. Acta, 1970, 53, 1677. [all data]
Franklin and Carroll, 1969
Franklin, J.L.; Carroll, S.R.,
Effect of molecular structure on ionic decomposition. II. An electron-impact study of 1,3-and 1,4-cyclohexadiene and 1,3,5-hexatriene,
J. Am. Chem. Soc., 1969, 91, 6564. [all data]
Worley, Webb, et al., 1979
Worley, S.D.; Webb, T.R.; Gibson, D.H.; Ong, T.-S.,
On the electronic structures of cyclobutadiene trimethylenemethane,
J. Organomet. Chem., 1979, 168, 16. [all data]
Heilbronner, Hoshi, et al., 1976
Heilbronner, E.; Hoshi, T.; von Rosenberg, J.L.; Hafner, K.,
Alkyl-induced, natural hypsochromic shifts of the 2A←2X and 2B←2X transitions of azulene and naphthalene radical cations,
Nouv. J. Chim., 1976, 1, 105. [all data]
Lias and Ausloos, 1985
Lias, S.G.; Ausloos, P.,
Structures of C6H7+ ions formed in unimolecular and bimolecular reactions,
J. Chem. Phys., 1985, 82, 3613. [all data]
Notes
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy 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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