Cyclopentene

• Formula: C₅H₈
• Molecular weight: 68.1170
• IUPAC Standard InChI: InChI=1S/C5H8/c1-2-4-5-3-1/h1-2H,3-5H2 Copy

  
• IUPAC Standard InChIKey: LPIQUOYDBNQMRZ-UHFFFAOYSA-N Copy
• CAS Registry Number: 142-29-0
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Information on this page:
  • Henry's Law data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
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  • Gas Phase Kinetics Database
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Henry's Law 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 by: Rolf Sander

Henry's Law constant (water solution)

k_H(T) = k°_H exp(d(ln(k_H))/d(1/T) ((1/T) - 1/(298.15 K)))
k°_H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(k_H))/d(1/T) = Temperature dependence constant (K)

Gas phase ion energetics 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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

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 C₅H₈⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

References

Go To: Top, Henry's Law 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.

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]

Harris, McKinnon, et al., 1979
Harris, D.; McKinnon, S.; Boyd, R.K., The origins of the base peak in the electron impact spectrum of limonene, Org. Mass Spectrom., 1979, 14, 265. [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]

Lossing and Traeger, 1975
Lossing, F.P.; Traeger, J.C., Stabilization in cyclopentadienyl, cyclopentenyl, and cyclopentyl cations, J. Am. Chem. Soc., 1975, 97, 1579. [all data]

Rang, Paldoia, et al., 1974
Rang, S.; Paldoia, P.; Talvari, A., Ionization potentials of unsaturated hydrocarbons. 2. Mono-substituted cyclopentenes and cyclohexenes, Eesti. NSV Tead. Akad. Toim., 1974, 354. [all data]

Holmes, 1974
Holmes, J.L., The mass spectra of isomeric hydrocarbons - II: The C₅H₈ isomers, spiropentane, cyclopentene, 1,3-pentadiene and isoprene; the mechanisms and energetics of their fragmentations, Org. Mass Spectrom., 1974, 8, 247. [all data]

Praet and Delwiche, 1970
Praet, M.-T.; Delwiche, J., Ionization energies of some cyclic molecules, Chem. Phys. Lett., 1970, 5, 546. [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]

Dewar and Worley, 1969
Dewar, M.J.S.; Worley, S.D., Photoelectron spectra of molecules. I. Ionization potentials of some organic molecules and their interpretation, J. Chem. Phys., 1969, 50, 654. [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]

Wiberg, Ellison, et al., 1976
Wiberg, K.B.; Ellison, G.B.; Wendoloski, J.J.; Brundle, C.R.; Kuebler, N.A., Electronic states of organic molecules. 3. Photoelectron spectra of cycloalkenes and methylenecycloalkanes, J. Am. Chem. Soc., 1976, 98, 7179. [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]

Bertoti, Cradock, et al., 1976
Bertoti, I.; Cradock, S.; Ebsworth, E.A.V.; Whiteford, R.A., Photoelectron spectra and transannular interactions in 1-silacyclopent-3-enes, J. Chem. Soc. Dalton Trans., 1976, 937. [all data]

Hentrich, Gunkel, et al., 1974
Hentrich, G.; Gunkel, E.; Klessinger, M., Photoelektronenspektren organischer verbindungen. 4. Photoelektronenspektren ungesattigter carbonylverbindungen, J. Mol. Struct., 1974, 21, 231. [all data]

Clary, Lewis, et al., 1974
Clary, D.C.; Lewis, A.A.; Morland, D.; Murrell, J.N.; Heilbronner, E., Ionization potentials of cycloalkenes, J. Chem. Soc. Faraday Trans. 2, 1974, 70, 1889. [all data]

Batich, Heilbronner, et al., 1974
Batich, C.; Heilbronner, E.; Rommel, E.; Semmelhack, M.F.; Foos, J.S., Equivalence of the energy gaps {DELTA}I(1,2) and {DELTA}E(1,2) between corresponding bands in the photoelectron (I) and electronic absorption (E) spectra of spiro[4.4]nonatetraene. An amusing consequence of spiroconjugation, J. Am. Chem. Soc., 1974, 96, 7662. [all data]

Lossing and Traeger, 1975, 2
Lossing, F.P.; Traeger, J.C., Free radicals by mass spectrometry XLVI. Heats of formation of C₅H₇ and C₅H₉ radicals and cations., J. Am. Chem. Soc., 1975, 19, 9. [all data]

Pignataro, Cassuto, et al., 1967
Pignataro, S.; Cassuto, A.; Lossing, F.P., Free radicals by mass spectrometry. XXXVI. Ionization potentials of conjugated and nonconjugated radicals, J. Am. Chem. Soc., 1967, 89, 3693. [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  d(ln(kH))/d(1/T)	Temperature dependence parameter for Henry's Law constant
  k°H	Henry's Law constant at 298.15K

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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