1,3-Cyclopentadiene

• Formula: C₅H₆
• Molecular weight: 66.1011
• IUPAC Standard InChI: InChI=1S/C5H6/c1-2-4-5-3-1/h1-4H,5H2 Copy

  
• IUPAC Standard InChIKey: ZSWFCLXCOIISFI-UHFFFAOYSA-N Copy
• CAS Registry Number: 542-92-7
• 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: Cyclopentadiene; Pentole; Pyropentylene; R-Pentine
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Ion clustering data
  • IR Spectrum
  • UV/Visible spectrum
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Gas Phase Kinetics Database
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Gas phase ion energetics data

Go To: Top, Mass spectrum (electron ionization), Gas Chromatography, References, Notes

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:
B - John E. Bartmess
MM - Michael M. Meot-Ner (Mautner)
LL - Sharon G. Lias and Joel F. Liebman
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 C₅H₆⁺ (ion structure unspecified)

Proton affinity at 298K

Gas basicity at 298K

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

 +  =

By formula: C₅H₅^- + H⁺ = C₅H₆

Mass spectrum (electron ionization)

Go To: Top, Gas phase ion energetics data, Gas Chromatography, 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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

Gas Chromatography

Go To: Top, 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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Kovats' RI, non-polar column, isothermal

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Kovats' RI, non-polar column, custom temperature program

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Kovats' RI, polar column, isothermal

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Kovats' RI, polar column, temperature ramp

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Normal alkane RI, non-polar column, isothermal

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Normal alkane RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, custom temperature program

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Lee's RI, non-polar column, temperature ramp

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References

Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), Gas Chromatography, 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]

Aue, Guidoni, et al., 2000
Aue, D.H.; Guidoni, M.; Betowski, L.D., Ab initio calculated gas-phase basicities of polynuclear aromatic hydrocarbons, Int. J. Mass Spectrom., 2000, 201, 283. [all data]

Kiselev, Sakhabutdinov, et al., 1992
Kiselev, V.D.; Sakhabutdinov, A.G.; Shakirov, I.M.; Zverev, V.V.; Konovalov, A.I., Bis reactants in Diels-Alder reactions. VII. Preparation and properties of polyadducts of reactions of bis(polymethylcyclopentadienes) and bis(maleimides), Zh. Org. Khim., 1992, 28, 2244. [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]

Holmes and McGillivray, 1971
Holmes, J.L.; McGillivray, D., The mass spectra of isomeric hydrocarbons-I: Norbornene and nortricyclene; The mechanisms and energetics of their fragmentations, Org. Mass Spectrom., 1971, 5, 1349. [all data]

Derrick, Asbrink, et al., 1971
Derrick, P.J.; Asbrink, L.; Edqvist, O.; Jonsson, B.-O.; Lindholm, E., Rydberg series in small molecules. XIII. Photoelectron spectroscopy and electronic structure of cyclopentadiene, Intern. J. Mass Spectrom. Ion Phys., 1971, 6, 203. [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]

Hedaya, Kent, et al., 1968
Hedaya, E.; Kent, M.E.; McNeil, D.W.; Lossing, F.P.; McAllister, T., The thermal rearrangement of phenylnitrene to cyanocyclopentadiene, Tetrahedron Lett., 1968, 30, 3415. [all data]

Dewar and Worley, 1968
Dewar, M.J.S.; Worley, S.D., Ionization potential of cis-1,3-butadiene, J. Chem. Phys., 1968, 49, 2454. [all data]

Bock and Kaim, 1980
Bock, H.; Kaim, W., Radical ions. 37. Ionization and one-electron oxidation of electron-rich silylalkyl olefins, J. Am. Chem. Soc., 1980, 102, 4429. [all data]

Cradock, Ebsworth, et al., 1975
Cradock, S.; Ebsworth, E.A.V.; Moretto, H.; Rankin, D.W.H., Photoelectron spectra and fluxional behaviour in some σ-cyclopentadienes, J. Chem. Soc. Dalton Trans., 1975, 390. [all data]

Cradock, Findlay, et al., 1974
Cradock, S.; Findlay, R.H.; Palmer, M.H., Bonding in methyl- and silyl-cyclopentadiene compounds: a study by photoelectron spectroscopy ab initio molecular-orbital calculations, J. Chem. Soc. Dalton Trans., 1974, 1650. [all data]

Occolowitz and White, 1968
Occolowitz, J.L.; White, G.L., Energetic considerations in the assignment of some fragment ion structures, Australian J. Chem., 1968, 21, 997. [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]

Dorman, 1965
Dorman, F.H., Second differential ionization-efficiency curves for fragment ions by electron impact, J. Chem. Phys., 1965, 43, 3507. [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]

Cumming and Kebarle, 1978
Cumming, J.B.; Kebarle, P., Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A), Can. J. Chem., 1978, 56, 1. [all data]

Engelking and Lineberger, 1977
Engelking, P.C.; Lineberger, W.C., Laser photoelectron spectrometry of C₅H₅-: A determination of the electron affinity and Jahn-Teller coupling in cyclopentadienyl, J. Chem. Phys., 1977, 67, 1412. [all data]

Diez, Guillen, et al., 1990
Diez, M.A.; Guillen, M.D.; Blanco, C.G.; Bermejo, J., Chromatographic study of methylcyclopentadiene dimers and iso-dimers and determination of their boiling points, J. Chromatogr., 1990, 508, 363-374, https://doi.org/10.1016/S0021-9673(00)91279-2 . [all data]

Safina, Poznyak, et al., 1989
Safina, L.R.; Poznyak, T.I.; Lisitsyn, D.M.; Kiseleva, E.V.; Kovalev, G.I., Selective gas-chromatographic determination of trace unsaturated and aromatic-hydrocarbons in complex-mixtures, J. Appl. Chem. USSR (Engl. Transl.), 1989, 44, 5, 749-754. [all data]

Papazova, Milina, et al., 1988
Papazova, D.; Milina, R.; Dimov, N., Comparative evaluation of retention of hydrocarbons present in the C₅-petroleum fraction of methylsilicone and squalane phases, Chromatographia, 1988, 25, 3, 177-180, https://doi.org/10.1007/BF02316441 . [all data]

Bermejo, Blanco, et al., 1987
Bermejo, J.; Blanco, C.G.; Diez, M.A.; Guillén, M.D., Kováts retention indices of selected mono and polycyclic olefins, J. Hi. Res. Chromatogr. Chromatogr. Comm., 1987, 10, 8, 461-463, https://doi.org/10.1002/jhrc.1240100809 . [all data]

Sojak, Ruman, et al., 1987
Sojak, L.; Ruman, J.; Janak, J., Characterization of Monoalkylcyclopentadiens by Retention-Structure Correlation in Capillary Gas Chromatography, J. Chromatogr., 1987, 391, 79-87, https://doi.org/10.1016/S0021-9673(01)94306-7 . [all data]

Bredael, 1982
Bredael, P., Retention indices of hydrocarbons on SE-30, J. Hi. Res. Chromatogr. Chromatogr. Comm., 1982, 5, 6, 325-328, https://doi.org/10.1002/jhrc.1240050610 . [all data]

Bajus, Veselý, et al., 1979
Bajus, M.; Veselý, V.; Leclercq, P.A.; Rijks, J.A., Steam cracking of hydrocarbons. 2. Pyrolysis of methylcyclohexane, Ind. Eng. Chem. Prod. Res. Dev., 1979, 18, 2, 135-142, https://doi.org/10.1021/i360070a012 . [all data]

Bajus, Veselý, et al., 1979, 2
Bajus, M.; Veselý, V.; Leclercq, P.A.; Rijks, J.A., Steam cracking of hydrocarbons. 1. Pyrolysis of heptane, Ind. Eng. Chem. Prod. Res. Dev., 1979, 18, 1, 30-37, https://doi.org/10.1021/i360069a007 . [all data]

Bogoslovsky, Anvaer, et al., 1978
Bogoslovsky, Yu.N.; Anvaer, B.I.; Vigdergauz, M.S., Chromatographic constants in gas chromatography (in Russian), Standards Publ. House, Moscow, 1978, 192. [all data]

Stopp, Engewald, et al., 1978
Stopp, I.; Engewald, W.; Kühn, H.; Welsch, Th., Molekülstruktur und retentionsverhalten. VIII. Zum gaschromatographischen retentionsverhalten von dicyclopentadienderivaten, J. Chromatogr., 1978, 147, 21-30, https://doi.org/10.1016/S0021-9673(00)85113-4 . [all data]

Schomburg and Dielmann, 1973
Schomburg, G.; Dielmann, G., Identification by means of retention parameters, J. Chromatogr. Sci., 1973, 11, 3, 151-159, https://doi.org/10.1093/chromsci/11.3.151 . [all data]

Hively and Hinton, 1968
Hively, R.A.; Hinton, R.E., Variation of the retention index with temperature on squalane substrates, J. Gas Chromatogr., 1968, 6, 4, 203-217, https://doi.org/10.1093/chromsci/6.4.203 . [all data]

Haagen-Smit Laboratory, 1997
Haagen-Smit Laboratory, Procedure for the detailed hydrocarbon analysis of gasolines by single column high efficiency (capillary) column gas chromatography, SOP NO. MLD 118, Revision No. 1.1, California Environmental Protection Agency, Air Resources Board, El Monte, California, 1997, 22. [all data]

Hoekman, 1993
Hoekman, S.K., Improved gas chromatography procedure for speciated hydrocarbon measurements of vehicle emissions, J. Chromatogr., 1993, 639, 2, 239-253, https://doi.org/10.1016/0021-9673(93)80260-F . [all data]

Umano and Shibamoto, 1987
Umano, K.; Shibamoto, T., Analysis of headspace volatiles from overheated beef fat, J. Agric. Food Chem., 1987, 35, 1, 14-18, https://doi.org/10.1021/jf00073a004 . [all data]

Bramston-Cook, 2013
Bramston-Cook, R., Kovats indices for C2-C13 hydrocarbons and selected oxygenated/halocarbons with 100 % dimethylpolysiloxane columns, 2013, retrieved from http://lotusinstruments.com/monographs/List .... [all data]

Zhang, Ding, et al., 2009
Zhang, X.; Ding, L.; Sun, Z.; Song, L.; Sun, T., Study on quantitative structure-retention relationships for hydrocarbons in FCC gasoline, Chromatographia, 2009, 70, 3/4, 511-518, https://doi.org/10.1365/s10337-009-1174-0 . [all data]

Chen, 2008
Chen, H.-F., Quantitative prediction of gas chromatography retention indices with support vector machines, radial basis neutral networks and multiple linear regression, Anal. Chim. Acta, 2008, 609, 1, 24-36, https://doi.org/10.1016/j.aca.2008.01.003 . [all data]

Perkin Elmer Instruments, 2002
Perkin Elmer Instruments, Detailed hydrocarbon analysis (DHAX) Model 4015, 2002, retrieved from http://www.perkinelmer.com/instruments. [all data]

Zenkevich, 1998
Zenkevich, I.G., Application of Methods of Molecular Dynamics in Chromato-Spectral Identification of ISomeric Products of Organic reactions (in Russian), Zh. Org. Khim., 1998, 34, 10, 1463-1470. [all data]

Waggott and Davies, 1984
Waggott, A.; Davies, I.W., Identification of organic pollutants using linear temperature programmed retention indices (LTPRIs) - Part II, 1984, retrieved from http://dwi.defra.gov.uk/research/completed-research/reports/dwi0383.pdf. [all data]

Shao, Wang, et al., 2006
Shao, X.; Wang, G.; Sun, Y.; Zhang, R.; Xie, K.; Liu, H., Determination and Characterization of the Pyrolysis Products of Isoprocarb by GC-MS, J. Chromatogr. Sci., 2006, 44, 3, 141-147, https://doi.org/10.1093/chromsci/44.3.141 . [all data]

Notes

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

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  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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