1,3,5,7-Cyclooctatetraene
- Formula: C8H8
- Molecular weight: 104.1491
- IUPAC Standard InChIKey: KDUIUFJBNGTBMD-BONZMOEMSA-N
- CAS Registry Number: 629-20-9
- 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: [8]Annulene; Cyclooctatetraene; UN 2358
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Gas phase ion energetics data
Go To: Top, 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
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 C8H8+ (ion structure unspecified)
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
0.570 ± 0.030 | N/A | Miller, Viggiano, et al., 2002 | B |
0.550 ± 0.020 | IMRE | Kato, Lee, et al., 1997 | B |
0.650 ± 0.043 | LPES | Wenthold, Hrovat, et al., 1996 | EA(D4h COT) = 1.099 ± 0.01 eV. D4H is TS, 10-11 kcal/mol above GS D8h; B |
0.58 ± 0.10 | CIDC | Denault, Chen, et al., 1998 | entropy of attachment: -14.7±13 eu; B |
<0.823919 | PD | Gygax, Peters, et al., 1979 | B |
0.577 ± 0.043 | ECD | Wentworth and Ristau, 1969 | B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.03 | PE | Fu and Dunbar, 1978 | LLK |
8.0 | PE | Batich, Bischof, et al., 1973 | LLK |
8.21 | PE | Dewar, Harget, et al., 1969 | Unpublished result of M.J.S. Dewar and S.D. Worley; RDSH |
8.04 | PE | Al-Joboury and Turner, 1964 | RDSH |
7.99 ± 0.02 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
8.43 | PE | Fu and Dunbar, 1978 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C3H3+ | 13.40 ± 0.10 | ? | EI | Franklin and Carroll, 1969 | RDSH |
C4H2+ | 17.11 ± 0.10 | 2C2H2+H2 | EI | Franklin and Carroll, 1969 | RDSH |
C4H3+ | 18.16 ± 0.25 | 2C2H2+H | EI | Franklin and Carroll, 1969 | RDSH |
C4H4+ | 15.10 ± 0.10 | 2C2H2 | EI | Franklin and Carroll, 1969 | RDSH |
C5H3+ | 16.41 ± 0.15 | C2H2+CH3? | EI | Franklin and Carroll, 1969 | RDSH |
C6H5+ | 14.58 ± 0.10 | C2H2+H | EI | Franklin and Carroll, 1969 | RDSH |
C6H6+ | 9.4 ± 0.05 | C2H2 | TRPI | Lifshitz and Malinovich, 1984 | LBLHLM |
C6H6+ | 9.70 ± 0.12 | C2H2 | EI | Franklin and Carroll, 1969 | RDSH |
C8H6+ | 11.70 ± 0.10 | H2 | EI | Franklin and Carroll, 1969 | RDSH |
C8H7+ | 10.90 ± 0.10 | H | EI | Franklin and Carroll, 1969 | RDSH |
De-protonation reactions
C8H7- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1601. ± 12. | kJ/mol | G+TS | Kato, Lee, et al., 1997 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1568. ± 10. | kJ/mol | IMRE | Kato, Lee, et al., 1997 | gas phase; B |
References
Go To: Top, 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.
Miller, Viggiano, et al., 2002
Miller, T.M.; Viggiano, A.A.; Miller, A.E.S.,
Electron attachment and detachment: Cyclooctatetraene,
J. Phys. Chem. A, 2002, 106, 43, 10200-10204, https://doi.org/10.1021/jp0205214
. [all data]
Kato, Lee, et al., 1997
Kato, S.; Lee, H.S.; Gareyev, R.; Wenthold, P.G.; Lineberger, W.C.; DePuy, C.H.; Bierbaum, V.M.,
Experimental and Computational Studies of the Structures and Energetics of Cyclooctatetraene and Its Derivatives,
J. Am. Chem. Soc., 1997, 119, 33, 7863, https://doi.org/10.1021/ja971433d
. [all data]
Wenthold, Hrovat, et al., 1996
Wenthold, P.G.; Hrovat, D.A.; Borden, W.T.; Lineberger, W.C.,
Transition State Spectroscopy of Cyclooctatetraene,
Science, 1996, 272, 5267, 1456, https://doi.org/10.1126/science.272.5267.1456
. [all data]
Denault, Chen, et al., 1998
Denault, J.W.; Chen, G.D.; Cooks, R.G.,
Electron affinity of 1,3,5,7-cyclooctatetraene determined by the kinetic method,
J. Am. Soc. Mass Spectrom., 1998, 9, 11, 1141-1145, https://doi.org/10.1016/S1044-0305(98)00092-0
. [all data]
Gygax, Peters, et al., 1979
Gygax, R.; Peters, H.L.; Brauman, J.I.,
Photodetachment of electrons from anions of high symmetry. Electron photodetachment spectra of the cycloctatetraenyl and perinaphthenyl anions,
J. Am. Chem. Soc., 1979, 101, 2567. [all data]
Wentworth and Ristau, 1969
Wentworth, W.E.; Ristau, W.,
Thermal Electron Attachment Involving a Change in Molecular Geometry,
J. Phys. Chem., 1969, 73, 7, 2126, https://doi.org/10.1021/j100727a005
. [all data]
Fu and Dunbar, 1978
Fu, E.W.; Dunbar, R.C.,
Photodissociation spectroscopy and structural rearrangements in ions of cyclooctatetraene, styrene and related molecules,
J. Am. Chem. Soc., 1978, 100, 2283. [all data]
Batich, Bischof, et al., 1973
Batich, C.; Bischof, P.; Heilbronner, E.,
The photoelectron spectra of cyclooctatetraene and its hydrogenated derivatives,
J. Electron Spectrosc. Relat. Phenom., 1973, 1, 333. [all data]
Dewar, Harget, et al., 1969
Dewar, M.J.S.; Harget, A.; Haselbach, E.,
Cyclooctatetraene and ions derived from it,
J. Am. Chem. Soc., 1969, 91, 7521. [all data]
Al-Joboury and Turner, 1964
Al-Joboury, M.I.; Turner, D.W.,
Molecular photoelectron spectroscopy. Part II. A summary of ionization potentials,
J. Chem. Soc., 1964, 4434. [all data]
Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J.,
Ionization potentials of some molecules,
J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]
Franklin and Carroll, 1969
Franklin, J.L.; Carroll, S.R.,
The effect of molecular structure on ionic decomposition. I. An electron impact study of seven C8H8 isomers,
J. Am. Chem. Soc., 1969, 91, 5940. [all data]
Lifshitz and Malinovich, 1984
Lifshitz, C.; Malinovich, Y.,
Time resolved photoionization mass spectrometry in the millisecond range,
Int. J. Mass Spectrom. Ion Processes, 1984, 60, 99. [all data]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy EA Electron affinity 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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