Bicyclo[4.2.0]octa-1,3,5-triene
- Formula: C8H8
- Molecular weight: 104.1491
- IUPAC Standard InChIKey: UMIVXZPTRXBADB-UHFFFAOYSA-N
- CAS Registry Number: 694-87-1
- 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: Benzocyclobutene; Benzocyclobutane; Benzocyclobutene, 1,2-dihydro-; Cardene; 1,2-Dihydrobenzocyclobutene
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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 by: 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
By formula: C8H8 = C8H8
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -13.1 | kcal/mol | Kin | Roth and Scholz, 1981 | gas phase |
ΔrH° | -10.6 ± 0.45 | kcal/mol | Cm | Roth, Biermann, et al., 1978 | liquid phase |
C8H8N2O = +
By formula: C8H8N2O = N2O + C8H8
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -9.85 ± 0.13 | kcal/mol | Kin | Oth, Olsen, et al., 1977 | liquid phase; solvent: THF; At 413 K |
By formula: 3H2 + C8H8 = C8H14
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -50.32 ± 0.03 | kcal/mol | Chyd | Turner, Goebel, et al., 1968 | liquid phase; solvent: Acetic acid |
By formula: C8H8 = C8H8
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 11.1 ± 0.2 | kcal/mol | Eqk | Roth, Ebbrecht, et al., 1988 | gas phase |
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 compiled as indicated in comments:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
View reactions leading to C8H8+ (ion structure unspecified)
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.74 ± 0.05 | EI | Franklin and Carroll, 1969 | RDSH |
8.66 ± 0.03 | PE | Heilbronner, Hoshi, et al., 1976 | Vertical value; LLK |
8.66 | PE | Brogli, Giovannini, et al., 1973 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C3H3+ | 14.16 ± 0.15 | ? | EI | Franklin and Carroll, 1969 | RDSH |
C4H2+ | 17.69 ± 0.30 | 2C2H2+H2 | EI | Franklin and Carroll, 1969 | RDSH |
C4H3+ | 18.68 ± 0.10 | 2C2H2+H | EI | Franklin and Carroll, 1969 | RDSH |
C4H4+ | 16.01 ± 0.15 | 2C2H2 | EI | Franklin and Carroll, 1969 | RDSH |
C5H3+ | 17.34 ± 0.10 | C2H2+CH3? | EI | Franklin and Carroll, 1969 | RDSH |
C6H5+ | 15.58 ± 0.10 | C2H2+H | EI | Franklin and Carroll, 1969 | RDSH |
C6H6+ | 11.55 ± 0.10 | C2H2 | EI | Franklin and Carroll, 1969 | RDSH |
C8H6+ | 11.84 ± 0.10 | H2 | EI | Franklin and Carroll, 1969 | RDSH |
C8H7+ | 11.94 ± 0.10 | H | EI | Franklin and Carroll, 1969 | RDSH |
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.
Roth and Scholz, 1981
Roth, W.R.; Scholz, B.P.,
Energy profile of the o-quinodimethane = benzocyclobutene equilibrium. Part 2.,
Chem. Ber., 1981, 114, 3741-3750. [all data]
Roth, Biermann, et al., 1978
Roth, W.R.; Biermann, M.; Dekker, H.; Jochems, R.; Mosselman, C.; Hermann, H.,
Energy profile of the o-quinodimethane-benzocyclobutene equilibrium,
Chem. Ber., 1978, 111, 3892-3903. [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]
Turner, Goebel, et al., 1968
Turner, R.B.; Goebel, P.; Mallon, B.J.; Doering, W.E.; Coburn, J.F., Jr.; Pomerantz, M.,
Heats of hydrogenation. VIII. Compounds with three- and four-membered rings,
J. Am. Chem. Soc., 1968, 90, 4315-4322. [all data]
Roth, Ebbrecht, et al., 1988
Roth, W.R.; Ebbrecht, T.; Beitat, A.,
o-Quinodimethane-benzocyclobutene equilibrium: oxygen trapping technique,
Chem. Ber., 1988, 121, 1357-1358. [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]
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]
Brogli, Giovannini, et al., 1973
Brogli, F.; Giovannini, E.; Heilbronner, E.; Schurter, R.,
Die photoelektronen spektren der benzocycloalkene,
Chem. Ber., 1973, 106, 961. [all data]
Notes
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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