1,3,5-Cycloheptatriene

• Formula: C₇H₈
• Molecular weight: 92.1384
• IUPAC Standard InChI: InChI=1S/C7H8/c1-2-4-6-7-5-3-1/h1-6H,7H2 Copy

  
• IUPAC Standard InChIKey: CHVJITGCYZJHLR-UHFFFAOYSA-N Copy
• CAS Registry Number: 544-25-2
• 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: Tropilidene; Cyclohepta-1,3,5-triene; Cycloheptatriene; Tropilidin; UN 2603
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Gas Phase Kinetics Database
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• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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Gas phase thermochemistry data

Go To: Top, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), 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
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

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:
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
CAL - James S. Chickos, William E. Acree, Jr., Joel F. Liebman, Students of Chem 202 (Introduction to the Literature of Chemistry), University of Missouri -- St. Louis
DH - Eugene S. Domalski and Elizabeth D. Hearing

Reduced pressure boiling point

Enthalpy of vaporization

Antoine Equation Parameters

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

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Enthalpy of fusion

Entropy of fusion

Enthalpy of phase transition

Entropy of phase transition

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), 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

View reactions leading to C₇H₈⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₇H₇^- +  =

By formula: C₇H₇^- + H⁺ = C₇H₈

Mass spectrum (electron ionization)

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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

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Roth, Bohm, et al., 1983
Roth, W.R.; Bohm, M.; Lenhartz, H-W.; Vogel, E., Heats of hydrogenation. Part 5. Resonance energy of bridged [10]annulenes, Angew. Chem., 1983, 95, 1011-1012. [all data]

Finke H.L., 1956
Finke H.L., Cycloheptane, cyclooctane, and 1,3,5-cycloheptatriene. Low-temperature thermal properties, vapor pressure, and derived chemical thermodynamic properties, J. Am. Chem. Soc., 1956, 78, 5469-5476. [all data]

Dorofeeva O.V., 1986
Dorofeeva O.V., Thermodynamic properties of twenty-one monocyclic hydrocarbons, J. Phys. Chem. Ref. Data, 1986, 15, 437-464. [all data]

Evans M.V., 1960
Evans M.V., Vibrational spectra and structure of the tropilidene molecule, J. Am. Chem. Soc., 1960, 82, 1876-1882. [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]

McCullough and Waddington, 1957
McCullough, J.P.; Waddington, G., Melting-point purity determinations: limitations as evidenced by calorimetric studies in the melting region, Anal. Chim. Acta, 1957, 17, 80. [all data]

Finke, Scott, et al., 1956
Finke, H.L.; Scott, D.W.; Gross, M.E.; Messerly, J.F.; Waddington, G., Cycloheptane, Cyclooctane and 1,3,5-Cycloheptatriene. Low Temperature Thermal Properties, Vapor Pressure and Derived Chemical Thermodynamic Prop., J. Am. Chem. Soc., 1956, 78, 5469. [all data]

Finke, Scott, et al., 1956, 2
Finke, H.L.; Scott, D.W.; Gross, M.E.; Messerly, J.F.; Waddington, G., Cycloheptane, cyclooctane and 1,3,5-cycloheptatriene. Low temperature thermal properties, vapor pressure and derived chemical thermodynamic properties, J. Am. Chem. Soc., 1956, 78, 5469-54. [all data]

Finke, Scott, et al., 1956, 3
Finke, H.L.; Scott, D.W.; Gross, M.E.; Messerly, J.F.; Waddington, G., Cycloheptane, cyclooctane and 1,3,5-cycloheptatriene. Low temperature thermal properties, vapor pressure and derived chemical thermodynamic properties, J. Am. Chem. Soc., 1956, 78, 5469-5476. [all data]

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [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]

Kkykj and Repas, 1973
Kkykj, J.; Repas, M., Petrochemia, 1973, 13, 179. [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]

Traeger and McLoughlin, 1978
Traeger, J.C.; McLoughlin, R.G., A photoionization study of the energetics of C₇H₇⁺ ion formed from C₇H₈ precursors, Int. J. Mass Spectrom. Ion Phys., 1978, 27, 319. [all data]

Hoffman, 1974
Hoffman, M.K., Hidden rearrangements in the mass spectral decomposition of cycloheptatriene, Z. Naturforsch. A:, 1974, 29, 1077. [all data]

Bodor, Dewar, et al., 1970
Bodor, N.; Dewar, M.J.S.; Worley, S.D., Photoelectron spectra of molecules. III. Ionization potentials of some cyclic hydrocarbons and their derivatives, and heats of formation and ionization potentials calculated by the MINDO SCF MO method, J. Am. Chem. Soc., 1970, 92, 19. [all data]

Akopyan and Vilesov, 1966
Akopyan, M.E.; Vilesov, F.I., A mass-spectrometric study of the photo-ionisation of benzene derivatives at wavelengths up to 885 A, Zh. Fiz. Khim., 1966, 40, 125, In original 63. [all data]

Price, Passmore, et al., 1963
Price, W.C.; Passmore, T.R.; Roessler, D.M., [Title unavailable], Faraday Discuss. Chem. Soc., 1963, 35, 238. [all data]

Muller, Schweig, et al., 1974
Muller, C.; Schweig, A.; Vermeer, H., Methode zur Berechnung induktiver und konjugativer Effekte - Andwendung auf Tropon, Angew. Chem., 1974, 86, 275. [all data]

Harrison, Haynes, et al., 1965
Harrison, A.G.; Haynes, P.; McLean, S.; Meyer, F., The mass spectra of methyl-substituted cyclopentadienes, J. Am. Chem. Soc., 1965, 87, 5099. [all data]

Lifshitz and Bauer, 1963
Lifshitz, C.; Bauer, S.H., Mass spectra of valence tautomers, J. Phys. Chem., 1963, 67, 1629. [all data]

Traeger and McLoughlin, 1977
Traeger, J.C.; McLoughlin, R.G., Threshold photoionization and dissociation of toluene and cycloheptatriene, J. Am. Chem. Soc., 1977, 99, 7351. [all data]

Harrison, Honnen, et al., 1960
Harrison, A.G.; Honnen, L.R.; Dauben, H.J., Jr.; Lossing, F.P., Free radicals by mass spectrometry. XX. Ionization potentials of cyclopentadienyl and cycloheptatrienyl radicals, J. Am. Chem. Soc., 1960, 82, 5593. [all data]

Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr., The gas phase acidity scale from methanol to phenol, J. Am. Chem. Soc., 1979, 101, 6047. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,gas	Constant pressure heat capacity of gas
  S°gas	Entropy of gas at standard conditions
  Tboil	Boiling point
  Ttriple	Triple point temperature
  ΔHtrs	Enthalpy of phase transition
  ΔStrs	Entropy of phase transition
  ΔfH°gas	Enthalpy of formation of gas 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
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