1,3,5,7-Cyclooctatetraene

• Formula: C₈H₈
• Molecular weight: 104.1491
• IUPAC Standard InChI: InChI=1S/C8H8/c1-2-4-6-8-7-5-3-1/h1-8H/b2-1-,3-1-,4-2-,5-3-,6-4-,7-5-,8-6-,8-7- Copy

  
• IUPAC Standard InChIKey: KDUIUFJBNGTBMD-BONZMOEMSA-N Copy
• 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
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Condensed phase thermochemistry data

Go To: Top, Phase change data, Reaction thermochemistry data, 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

Phase change data

Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, 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:
BS - Robert L. Brown and Stephen E. Stein
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
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Enthalpy of fusion

Entropy of fusion

Reaction thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, 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

C₈H₇^- +  =

By formula: C₈H₇^- + H⁺ = C₈H₈

4 +  =

By formula: 4H₂ + C₈H₈ = C₈H₁₆

=

By formula: C₈H₈ = C₈H₈

=

By formula: C₈H₈ = c₈H₈

Gas phase ion energetics data

Go To: Top, Condensed phase thermochemistry data, Phase change data, 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:
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

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₈H₇^- +  =

By formula: C₈H₇^- + H⁺ = C₈H₈

References

Go To: Top, Condensed phase thermochemistry data, Phase change data, 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.

Prosen, Johnson, et al., 1950
Prosen, E.J.; Johnson, W.H.; Rossini, F.D., Heat of combustion and formation of 1,3,5,7-cyclooctatetraene and its heat of isomerization of styrene, J. Am. Chem. Soc., 1950, 72, 626-629. [all data]

Springall, White, et al., 1954
Springall, H.D.; White, T.R.; Cass, R.C., Heats of combustion and molecular structure Part 1.- The resonance energy and structure of cyclo-octateraene, Trans. Faraday Soc., 1954, 50, 815. [all data]

Scott, Gross, et al., 1949
Scott, D.W.; Gross, M.E.; Oliver, G.D.; Huffman, H.M., Cycloöctatetraene: low-temperature heat capacity, heat of fusion, heat of vaporization, vapor pressure and entropy, J. Am. Chem. Soc., 1949, 71, 1634-1636. [all data]

Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc., Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]

Reppe, Schlichting, et al., 1948
Reppe, W.; Schlichting, O.; Klager, K.; Toepel, T., Cyclizing Polymerization of Acetylene I. Cyclooctatetraene, Justus Liebigs Ann. Chem., 1948, 560, 1-92. [all data]

Cope and Bailey, 1948
Cope, A.C.; Bailey, W.J., Cyclic Polyolefins II. Synthesis of Cyclooctatetraene from Chloroprene, J. Am. Chem. Soc., 1948, 70, 2305. [all data]

Scott, Gross, et al., 1949, 2
Scott, D.W.; Gross, M.E.; Oliver, G.D.; Huffman, H.M., Cyclooctatetraene: low-temperature heat capacity, heat of fusion, heat of vaporization, vapor pressure and entropy, J. Am. Chem. Soc., 1949, 71, 1634. [all data]

Scott, Gross, et al., 1949, 3
Scott, D.W.; Gross, M.E.; Oliver, G.D.; Huffman, H.M., Cyclooctatetraene: Low-temperature heat capacity, heat of fusion, heat of vaporization, vapor pressure and entropy, J. Am. Chem. Soc., 1949, 71, 1634-16. [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [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]

Turner, Meador, et al., 1957
Turner, R.B.; Meador, W.R.; Doering, W.E.; Knox, L.H.; Mayer, J.R.; Wiley, D.W., Heats of hydrogenation. III. Hydrogenation of cycllooctatetraene and of some seven-membered non-benzenoid aromatic compounds, J. Am. Chem. Soc., 1957, 79, 4127-4133. [all data]

Prosen, Johnson, et al., 1947
Prosen, E.J.; Johnson, W.H.; Rossini, F.D., Heat of combustion and formation of 1,3,5,7-cyclooctatetraene and its heat of isomerization to styrene, J. Am. Chem. Soc., 1947, 69, 2068-2069. [all data]

Squillacote and Bergman, 1986
Squillacote, M.E.; Bergman, A., Trapping of 1,3,5,7-cyclooctatetraene valence tautomers. Thermodynamic stability of bicyclo[4.2.0]octa-2,4,7-triene, J. Org. Chem., 1986, 51, 3910-3911. [all data]

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]

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, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  EA	Electron affinity
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.