1,3-Cyclopentadiene
- Formula: C5H6
- Molecular weight: 66.1011
- IUPAC Standard InChIKey: ZSWFCLXCOIISFI-UHFFFAOYSA-N
- 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
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Condensed phase thermochemistry data
Go To: Top, Phase change data, Gas phase ion energetics data, 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: Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
S°liquid | 182.7 | J/mol*K | N/A | Lebedev and Lityagov, 1977 |
Constant pressure heat capacity of liquid
Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
115.3 | 298.15 | Lebedev and Lityagov, 1977 | T = 14 to 330 K. |
Phase change data
Go To: Top, Condensed phase thermochemistry data, Gas phase ion energetics data, 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:
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
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 314. ± 2. | K | AVG | N/A | Average of 8 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 183.15 | K | N/A | Murphy and Duggan, 1949 | Uncertainty assigned by TRC = 10. K; TRC |
Tfus | 188. | K | N/A | Staudinger, 1926 | Uncertainty assigned by TRC = 3. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 176.60 | K | N/A | Lebedev and Lityagov, 1977, 2 | Uncertainty assigned by TRC = 0.05 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 29. | kJ/mol | V | Rogers, 1972 | ALS |
ΔvapH° | 28.4 ± 0.3 | kJ/mol | V | Hull, Reid, et al., 1965 | ALS |
ΔvapH° | 28.4 ± 0.3 | kJ/mol | MM | Hull, Reid, et al., 1965, 2 | Based on data from 291. to 314. K.; AC |
ΔvapH° | 29.7 | kJ/mol | N/A | Hull, Reid, et al., 1965, 2 | Based on data from 273. to 287. K. See also Barrett and Burrage, 1932.; AC |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
28.1 | 302. | A,MM | Stephenson and Malanowski, 1987 | Based on data from 291. to 314. K. See also Hull, Reid, et al., 1965, 2.; AC |
28.2 | 286. | N/A | Lesteva, Ogorodnikov, et al., 1967 | Based on data from 271. to 314. K. See also Boublik, Fried, et al., 1984.; AC |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (bar)
T = temperature (K)
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Temperature (K) | A | B | C | Reference | Comment |
---|---|---|---|---|---|
271.3 to 314. | 2.65373 | 531.826 | -113.863 | Lesteva, Ogoradnikov, et al., 1967 | Coefficents calculated by NIST from author's data. |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
8.010 | 176.60 | Lebedev and Lityagov, 1977 | DH |
8.01 | 176.6 | Domalski and Hearing, 1996 | AC |
Entropy of fusion
ΔfusS (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
45.4 | 176.60 | Lebedev and Lityagov, 1977 | DH |
Gas phase ion energetics data
Go To: Top, Condensed phase thermochemistry data, Phase change data, 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)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 8.57 ± 0.01 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 821.6 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 798.4 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Proton affinity at 298K
Proton affinity (kJ/mol) | Reference | Comment |
---|---|---|
828.0 | Aue, Guidoni, et al., 2000 | Experimental literature data re-evaluated by the authors using ab initio protonation entropies; MM |
Gas basicity at 298K
Gas basicity (review) (kJ/mol) | Reference | Comment |
---|---|---|
798.3 | Aue, Guidoni, et al., 2000 | Experimental literature data re-evaluated by the authors using ab initio protonation entropies; MM |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.44 | PE | Kiselev, Sakhabutdinov, et al., 1992 | LL |
8.58 ± 0.02 | PE | Bieri, Burger, et al., 1977 | LLK |
8.56 ± 0.01 | EI | Holmes and McGillivray, 1971 | LLK |
8.57 ± 0.01 | PI | Derrick, Asbrink, et al., 1971 | LLK |
8.57 ± 0.01 | PI | Demeo and El-Sayed, 1970 | RDSH |
9.0 | EI | Hedaya, Kent, et al., 1968 | RDSH |
8.55 | PI | Dewar and Worley, 1968 | RDSH |
8.53 | PE | Kiselev, Sakhabutdinov, et al., 1992 | Vertical value; LL |
8.61 | PE | Bock and Kaim, 1980 | Vertical value; LLK |
8.6 | PE | Cradock, Ebsworth, et al., 1975 | Vertical value; LLK |
8.56 | PE | Cradock, Findlay, et al., 1974 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C5H5+ | 12.62 | H | EI | Occolowitz and White, 1968 | RDSH |
C5H5+ | 12.9 | H | EI | Harrison, Haynes, et al., 1965 | RDSH |
C5H5+ | 11.9 ± 0.5 | H | EI | Dorman, 1965 | RDSH |
C5H5+ | 12.6 | H | EI | Harrison, Honnen, et al., 1960 | RDSH |
De-protonation reactions
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1481. ± 9.2 | kJ/mol | G+TS | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrH° | 1485. ± 12. | kJ/mol | G+TS | Cumming and Kebarle, 1978 | gas phase; B |
ΔrH° | 1495. ± 8.4 | kJ/mol | D-EA | Engelking and Lineberger, 1977 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1455. ± 8.4 | kJ/mol | IMRE | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrG° | 1459. ± 8.4 | kJ/mol | IMRE | Cumming and Kebarle, 1978 | gas phase; B |
References
Go To: Top, 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.
Lebedev and Lityagov, 1977
Lebedev, B.V.; Lityagov, V.Ya.,
Thermodynamics of polypentenamer synthesis reactions,
Vysokomol. Soedin., 1977, B19, 558-560. [all data]
Murphy and Duggan, 1949
Murphy, M.T.; Duggan, A.C.,
Pyrolysis of Butadiene,
J. Am. Chem. Soc., 1949, 71, 3347. [all data]
Staudinger, 1926
Staudinger, H.,
Ber. Dtsch. Chem. Ges., 1926, 59, 3019. [all data]
Lebedev and Lityagov, 1977, 2
Lebedev, B.V.; Lityagov, V.Ya.,
Thermodynamics of polypentenamer synthesis reactions crystalline polytetrahydrofuran at 0 K,
Vysokomol. Soedin., Ser. B, 1977, 19, 558. [all data]
Rogers, 1972
Rogers, F.E.,
Thermochemistry of the Diels-Alder reactions. II. Heat of addition of several dienes to tetracyanoethylene,
J. Phys. Chem., 1972, 76, 106-109. [all data]
Hull, Reid, et al., 1965
Hull, H.S.; Reid, A.F.; Turnbull, A.G.,
Vapour pressures of cyclopentadiene and bis(cyclopentadienyl)magnesium,
Aust. J. Chem., 1965, 18, 249. [all data]
Hull, Reid, et al., 1965, 2
Hull, HS; Reid, AF; Turnbull, AG,
Vapour pressures of cyclopentadiene and Bis(cyclopentadienyl)magnesium,
Aust. J. Chem., 1965, 18, 2, 249-621, https://doi.org/10.1071/CH9650249
. [all data]
Barrett and Burrage, 1932
Barrett, E.G.V.; Burrage, L.J.,
Some Observations on the Transformation of Cyclopentadiene into its Dimeride.,
J. Phys. Chem., 1932, 37, 8, 1029-1035, https://doi.org/10.1021/j150350a007
. [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]
Lesteva, Ogorodnikov, et al., 1967
Lesteva, T.M.; Ogorodnikov, S.K.; Morozova, A.I.,
Zh. Prikl. Khim. (Leningrad), 1967, 40, 4, 891. [all data]
Boublik, Fried, et al., 1984
Boublik, T.; Fried, V.; Hala, E.,
The Vapour Pressures of Pure Substances: Selected Values of the Temperature Dependence of the Vapour Pressures of Some Pure Substances in the Normal and Low Pressure Region, 2nd ed., Elsevier, New York, 1984, 972. [all data]
Lesteva, Ogoradnikov, et al., 1967
Lesteva, T.M.; Ogoradnikov, S.K.; Morozova, A.,
Kinetics of Dimerisation of Cyclopentadiene and Equilibrium of Liquid-Steam in System of Isoprene-Cyclopentadiene,
Zh. Prikl. Khim. (Leningrad), 1967, 40, 891-894. [all data]
Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D.,
Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III,
J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985
. [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]
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]
Notes
Go To: Top, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy Cp,liquid Constant pressure heat capacity of liquid IE (evaluated) Recommended ionization energy S°liquid Entropy of liquid at standard conditions Tboil Boiling point Tfus Fusion (melting) point Ttriple Triple point temperature ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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