Cyclopentene
- Formula: C5H8
- Molecular weight: 68.1170
- IUPAC Standard InChIKey: LPIQUOYDBNQMRZ-UHFFFAOYSA-N
- 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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Gas phase thermochemistry data
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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
DRB - Donald R. Burgess, Jr.
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | 36. | kJ/mol | Chyd | Allinger, Dodziuk, et al., 1982 | ALS |
ΔfH°gas | 34. | kJ/mol | Eqk | Furuyama, Golden, et al., 1970 | ALS |
ΔfH°gas | 32.6 | kJ/mol | N/A | Labbauf and Rossini, 1961 | Value computed using ΔfHliquid° value of 4.27±0.63 kj/mol from Labbauf and Rossini, 1961 and ΔvapH° value of 28.37 kj/mol from missing citation.; DRB |
ΔfH°gas | 33.2 | kJ/mol | N/A | Epstein, Pitzer, et al., 1949 | Value computed using ΔfHliquid° value of 4.85±0.67 kj/mol from Epstein, Pitzer, et al., 1949 and ΔvapH° value of 28.37 kj/mol from missing citation.; DRB |
Quantity | Value | Units | Method | Reference | Comment |
S°gas | 289.66 | J/mol*K | N/A | Beckett C.W., 1948 | GT |
Constant pressure heat capacity of gas
Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
35.92 | 50. | Dorofeeva O.V., 1986 | Although S(298.15 K) value is 1.6 J/mol*K larger than that obtained from calorimetric data [ Beckett C.W., 1948] and calculated in previous works [ Beckett C.W., 1948, Epstein M.B., 1949, Furuyama S., 1970, Draeger J.A., 1983], it is selected here because of using the most reliable vibrational frequencies in [ Dorofeeva O.V., 1986]. The recommended thermodynamic functions are in good agreement with results of detail force-field calculations [ Lenz T.G., 1989, Lenz T.G., 1990]. Discrepancies with above mentioned calculations amount to 1.6-9.1 and 0.8-6.2 J/mol*K for S(T) and Cp(T), respectively.; GT |
40.37 | 100. | ||
45.72 | 150. | ||
54.74 | 200. | ||
73.82 | 273.15 | ||
81.3 ± 2.0 | 298.15 | ||
81.84 | 300. | ||
112.08 | 400. | ||
138.99 | 500. | ||
161.38 | 600. | ||
179.95 | 700. | ||
195.52 | 800. | ||
208.71 | 900. | ||
219.96 | 1000. | ||
229.60 | 1100. | ||
237.88 | 1200. | ||
245.02 | 1300. | ||
251.19 | 1400. | ||
256.53 | 1500. |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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: 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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -112.7 ± 0.54 | kJ/mol | Chyd | Allinger, Dodziuk, et al., 1982 | liquid phase; solvent: Hexane |
ΔrH° | -112. ± 0.8 | kJ/mol | Chyd | Roth and Lennartz, 1980 | liquid phase; solvent: Cyclohexane |
ΔrH° | -109.0 ± 1.8 | kJ/mol | Chyd | Turner, Jarrett, et al., 1973 | liquid phase; solvent: Acetic acid |
ΔrH° | -110. ± 0.8 | kJ/mol | Chyd | Rogers and McLafferty, 1971 | liquid phase; solvent: Hydrocarbon |
ΔrH° | -111.6 ± 0.3 | kJ/mol | Chyd | Dolliver, Gresham, et al., 1937 | gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -112.6 ± 0.3 kJ/mol; At 355 °K |
By formula: C5H8 + C2HF3O2 = C7H9F3O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -38.35 ± 0.18 | kJ/mol | Cac | Wiberg, Wasserman, et al., 1985 | liquid phase; solvent: Trifluoroacetic acid; Trifluoroacetolysis |
By formula: C5H8 + Br2 = C5H8Br2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -119.7 ± 2.5 | kJ/mol | Cm | Lister, 1941 | gas phase; Halogenation at 27 C |
By formula: C5H10 + I2 = 2HI + C5H8
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 102.1 | kJ/mol | Eqk | Furuyama, Golden, et al., 1970 | gas phase |
By formula: 2HI + C5H6 = C5H8 + I2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -89.5 | kJ/mol | Eqk | Furuyama, Golden, et al., 1970 | gas phase |
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)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 9.01 ± 0.01 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 766.3 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 733.8 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.18 | PE | Kimura, Katsumata, et al., 1981 | LLK |
9.1 | EI | Harris, McKinnon, et al., 1979 | LLK |
9.01 ± 0.02 | PE | Bieri, Burger, et al., 1977 | LLK |
9.00 | EI | Lossing and Traeger, 1975 | LLK |
9.02 ± 0.01 | PE | Rang, Paldoia, et al., 1974 | LLK |
9.00 | EI | Holmes, 1974 | LLK |
9.01 ± 0.01 | PE | Praet and Delwiche, 1970 | RDSH |
9.02 ± 0.01 | PI | Demeo and El-Sayed, 1970 | RDSH |
9.01 | PE | Bischof and Heilbronner, 1970 | RDSH |
9.00 | PE | Dewar and Worley, 1969 | RDSH |
9.01 ± 0.01 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
9.20 | PE | Wiberg, Ellison, et al., 1976 | Vertical value; LLK |
9.01 ± 0.03 | PE | Heilbronner, Hoshi, et al., 1976 | Vertical value; LLK |
9.17 | PE | Bertoti, Cradock, et al., 1976 | Vertical value; LLK |
9.12 | PE | Hentrich, Gunkel, et al., 1974 | Vertical value; LLK |
9.18 | PE | Clary, Lewis, et al., 1974 | Vertical value; LLK |
9.20 | PE | Batich, Heilbronner, et al., 1974 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C4H5+ | 11.83 | CH3 | EI | Holmes, 1974 | LLK |
C5H7+ | 9.00 | H | EI | Lossing and Traeger, 1975, 2 | LLK |
C5H7+ | 10.98 | H | EI | Lossing and Traeger, 1975 | LLK |
C5H7+ | 10.98 | H | EI | Holmes, 1974 | LLK |
C5H7+ | 11.19 | H | EI | Pignataro, Cassuto, et al., 1967 | RDSH |
IR Spectrum
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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
Gas Phase Spectrum
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Additional Data
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Download spectrum in JCAMP-DX format.
Owner | NIST Standard Reference Data Program Collection (C) 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | NIST Mass Spectrometry Data Center |
State | gas |
Instrument | HP-GC/MS/IRD |
Mass spectrum (electron ionization)
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, UV/Visible spectrum, 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
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Due to licensing restrictions, this spectrum cannot be downloaded.
Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | Japan AIST/NIMC Database- Spectrum MS-NW-3720 |
NIST MS number | 227659 |
UV/Visible spectrum
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, 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: Victor Talrose, Eugeny B. Stern, Antonina A. Goncharova, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina
Spectrum
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Additional Data
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Download spectrum in JCAMP-DX format.
Source | Pickett, Muntz, et al., 1951 |
---|---|
Owner | INEP CP RAS, NIST OSRD Collection (C) 2007 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
Origin | INSTITUTE OF ENERGY PROBLEMS OF CHEMICAL PHYSICS, RAS |
Source reference | RAS UV No. 47 |
Instrument | Hilger fluorite prism spectrograph |
Melting point | -135.1 |
Boiling point | 44.2 |
References
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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]
Furuyama, Golden, et al., 1970
Furuyama, S.; Golden, D.M.; Benson, S.W.,
Thermochemistry of cyclopentene and cyclopentadiene from studies of gas-phase equilibria,
J. Chem. Thermodyn., 1970, 2, 161-169. [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]
Epstein, Pitzer, et al., 1949
Epstein, M.B.; Pitzer, K.S.; Rossini, F.D.,
Heats, equilibrium constants, and free energies of formation of cyclopentene and cyclohexene,
J. Res. NBS, 1949, 42, 379-382. [all data]
Beckett C.W., 1948
Beckett C.W.,
The thermodynamic properties and molecular structure of cyclopentene and cyclohexene,
J. Am. Chem. Soc., 1948, 70, 4227-4230. [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]
Epstein M.B., 1949
Epstein M.B.,
Heats, equilibrium constants, and free energies of formation of cyclopentene and cyclohexene,
J. Res. Nat. Bur. Stand., 1949, 42, 379-382. [all data]
Furuyama S., 1970
Furuyama S.,
Thermochemistry of cyclopentene and cyclopentadiene from studies of gas-phase equilibria,
J. Chem. Thermodyn., 1970, 2, 161-169. [all data]
Draeger J.A., 1983
Draeger J.A.,
Chemical thermodynamic properties of molecules that undergo inversion. I. Aniline, methylamine, cyclopropylamine, and cyclopentene,
J. Chem. Thermodyn., 1983, 15, 367-376. [all data]
Lenz T.G., 1989
Lenz T.G.,
Force-field calculations giving accurate conformation, Hf(T), S(T), and Cp(T) for unsaturated acyclic and cyclic hydrocarbons,
J. Phys. Chem., 1989, 93, 1588-1592. [all data]
Lenz T.G., 1990
Lenz T.G.,
Force field calculation of equilibrium thermodynamic properties: Diels-Alder reaction of 1,3-butadiene and ethylene and Diels-Alder dimerization of 1,3-butadiene,
J. Comput. Chem., 1990, 11, 351-360. [all data]
Roth and Lennartz, 1980
Roth, W.R.; Lennartz, H.W.,
Heats of hydrogenation. I. Determination of heats of hydrogenation with an isothermal titration calorimeter,
Chem. Ber., 1980, 113, 1806-1817. [all data]
Turner, Jarrett, et al., 1973
Turner, R.B.; Jarrett, A.D.; Goebel, P.; Mallon, B.J.,
Heats of hydrogenation. 9. Cyclic acetylenes and some miscellaneous olefins,
J. Am. Chem. Soc., 1973, 95, 790-792. [all data]
Rogers and McLafferty, 1971
Rogers, D.W.; McLafferty, F.J.,
A new hydrogen calorimeter. Heats of hydrogenation of allyl and vinyl unsaturation adjacent to a ring,
Tetrahedron, 1971, 27, 3765-3775. [all data]
Dolliver, Gresham, et al., 1937
Dolliver, M.a.; Gresham, T.L.; Kistiakowsky, G.B.; Vaughan, W.E.,
Heats of organic reactions. V. Heats of hydrogenation of various hydrocarbons,
J. Am. Chem. Soc., 1937, 59, 831-841. [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]
Wiberg, Wasserman, et al., 1985
Wiberg, K.B.; Wasserman, D.J.; Martin, E.J.; Murcko, M.A.,
Enthalpies of hydration of alkenes. 3. Cycloalkenes,
J. Am. Chem. Soc., 1985, 107, 6019-6022. [all data]
Lister, 1941
Lister, M.W.,
Heats of organic reactions. X. Heats of bromination of cyclic olefins,
J. Am. Chem. Soc., 1941, 63, 143-149. [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]
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]
Pickett, Muntz, et al., 1951
Pickett, L.W.; Muntz, M.; McPherson, E.M.,
Vacuum ultraviolet absorption spectra of cyclic compounds. I. Cyclohexane, cyclohexene, cyclopentane, Cyclopentene and benzene,
J. Am. Chem. Soc., 1951, 73, 4862-4865. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, References
- Symbols used in this document:
AE Appearance energy Cp,gas Constant pressure heat capacity of gas IE (evaluated) Recommended ionization energy S°gas Entropy of gas at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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