Cyclopentene
- Formula: C5H8
- Molecular weight: 68.1170
- IUPAC Standard InChI: InChI=1S/C5H8/c1-2-4-5-3-1/h1-2H,3-5H2
- IUPAC Standard InChIKey: LPIQUOYDBNQMRZ-UHFFFAOYSA-N
- CAS Registry Number: 142-29-0
- Chemical structure:
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Reaction thermochemistry data
Go To: Top, 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 |
+
= 2
+
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 |
2 +
=
+
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 |
References
Go To: Top, Reaction thermochemistry 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]
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]
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]
Notes
Go To: Top, Reaction thermochemistry data, References
- Symbols used in this document:
ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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