Cyclopentene, 1-methyl-

• Formula: C₆H₁₀
• Molecular weight: 82.1436
• IUPAC Standard InChI: InChI=1S/C6H10/c1-6-4-2-3-5-6/h4H,2-3,5H2,1H3 Copy

  
• IUPAC Standard InChIKey: ATQUFXWBVZUTKO-UHFFFAOYSA-N Copy
• CAS Registry Number: 693-89-0
• 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: 1-Methyl-1-cyclopentene; 1-Methylcyclopentene; 1-Methyl-1-cyclopentane; Cyc1opentene,l-methyl-; 1-Cyclopentene, 1-methyl; 1-Methylcyclopentene-1
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • Computational Chemistry Comparison and Benchmark Database
  • Gas Phase Kinetics Database
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Gas phase thermochemistry 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.

Condensed phase thermochemistry 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:
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

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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
DRB - Donald R. Burgess, Jr.

Reduced pressure boiling point

Enthalpy of vaporization

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

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 C₆H₁₀⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

References

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

Allinger, Dodziuk, et al., 1982
Allinger, N.L.; Dodziuk, H.; Rogers, D.W.; Naik, S.N., Heats of hydrogenation and formation of some 5-membered ring compounds by molecular mechanics calculations and direct measurements, Tetrahedron, 1982, 38, 1593-1597. [all data]

Fuchs and Peacock, 1979
Fuchs, R.; Peacock, L.A., Heats of vaporization and gaseous heats of formation of some five- and six-membered ring alkenes, Can. J. Chem., 1979, 57, 2302-2304. [all data]

Good and Smith, 1969
Good, W.D.; Smith, N.K., Enthalpies of combustion of toluene, benzene, cyclohexane, cyclohexene, methylcyclopentane, 1-methylcyclopentene, and n-hexane, J. Chem. Eng. Data, 1969, 14, 102-106. [all data]

Labbauf and Rossini, 1961
Labbauf, A.; Rossini, F.D., Heats of combustion, formation, and hydrogenation of 14 selected cyclomonoolefin hydrocarbons, J. Phys. Chem., 1961, 65, 476-480. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [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]

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]

Dykyj, 1972
Dykyj, J., Petrochemia, 1972, 12, 1, 13. [all data]

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]

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]

Praet, 1970
Praet, M.-Th., Ionisation et dissociation du 1-methyl-cyclopentene, du methylenecyclopentane et de quelques isomeres par impact d'electrons et de photons, Org. Mass Spectrom., 1970, 4, 65. [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]

Winters and Collins, 1969
Winters, R.E.; Collins, J.H., Mass spectrometric studies of structural isomers. II.Mono- and bicyclic C₆H₁₀ molecules, Org. Mass Spectrom., 1969, 2, 299. [all data]

Shikhmamedbekova, Aslanov, et al., 1970
Shikhmamedbekova, A.Z.; Aslanov, F.A.; Gadzhiev, M.M.; Gulamova, T.E.; Akhmedova, F.N., Mass spectrometric study of methylene cycloalkenes, Dokl. Phys. Chem., 1970, 26, 34. [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]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

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