Cyclobutane, methylene-

• Formula: C₅H₈
• Molecular weight: 68.1170
• IUPAC Standard InChI: InChI=1S/C5H8/c1-5-3-2-4-5/h1-4H2 Copy

  
• IUPAC Standard InChIKey: QIRVGKYPAOQVNP-UHFFFAOYSA-N Copy
• CAS Registry Number: 1120-56-5
• 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.
• Species with the same structure:
  • Cyclobutane, methylene-
• Other names: Methylenecyclobutane
• 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
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Gas Phase Kinetics Database
• Options:
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• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, 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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, 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 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

Go To: Top, Gas phase thermochemistry data, 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
DRB - Donald R. Burgess, Jr.
AC - William E. Acree, Jr., James S. Chickos
DH - Eugene S. Domalski and Elizabeth D. Hearing

Reduced pressure boiling point

Enthalpy of vaporization

Enthalpy of fusion

Entropy of fusion

Enthalpy of phase transition

Entropy of phase transition

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, 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 compiled as indicated in comments:
B - John E. Bartmess
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)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₅H₇^- +  =

By formula: C₅H₇^- + H⁺ = C₅H₈

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.

Roth, Adamczak, et al., 1991
Roth, W.R.; Adamczak, O.; Breuckmann, R.; Lennartz, H.-W.; Boese, R., Die Berechnung von Resonanzenergien; das MM2ERW-Kraftfeld, Chem. Ber., 1991, 124, 2499-2521. [all data]

Good, Moore, et al., 1974
Good, W.D.; Moore, R.T.; Osborn, A.G.; Douslin, D.R., The enthalpies of formation of ethylcyclobutane, methylenecyclobutane, and 1,1-dimethylcyclopropane, J. Chem. Thermodyn., 1974, 6, 303-310. [all data]

Finke H.L., 1981
Finke H.L., Thermodynamic properties of cyclopropylamine, cyclopentylamine, and methylenecyclobutane, J. Chem. Thermodyn., 1981, 13, 345-355. [all data]

Andreevskii D.N., 1983
Andreevskii D.N., Value of the S(298.15) entropy of methylenecyclobutane in the gaseous state, Zh. Fiz. Khim., 1983, 57, 2109. [all data]

Andreevskii D.N., 1976
Andreevskii D.N., The similar structures method in thermodynamics of C3-C5 methylenecycloalkanes, Zh. Strukt. Khim., 1976, 17, 51-57. [all data]

Finke, Messerly, et al., 1981
Finke, H.L.; Messerly, J.F.; Lee-Bechtold, S.H., Thermodynamic properties of cyclopropylamine, cyclopentylamine, and methylenecyclobutane, J. Chem. Thermodyn., 1981, 13, 345-355. [all data]

Lebedev, Tsvetkova, et al., 1978
Lebedev, B.V.; Tsvetkova, L.Ya.; Rabinovich, I.B.; Finkel'shtein, E.Sh.; Strel'chik, B.S., Thermodynamic characteristics of methylenecyclobutane, Termodin. Org. Soedin., 1978, (7), 3-7. [all data]

Lebedev, Tsvetkova, et al., 1978, 2
Lebedev, B.V.; Tsvetkova, L.Ya.; Rabinovich, I.B., Thermodynamics of methylenecyclobutane, J. Chem. Thermodyn., 1978, 10, 809-815. [all data]

Lebedev, Lebedev, et al., 1975
Lebedev, B.V.; Lebedev, N.K.; Kiparisova, Y.G.; Tsvetkova, L.Ya.; Rabinovich, I.B., Thermodynamics of methylenecyclobutane and 1,5-cyclooctadiene, Quatrieme Conference International de Thermodynamique Chimique, 1975, II, Thermophysique (capacites thermiques) pp. [all data]

Slabey, 1946
Slabey, V.A., J. Am. Chem. Soc., 1946, 68, 1335. [all data]

Finke, Messerly, et al., 1981, 2
Finke, H.L.; Messerly, J.F.; Lee-Bechtold, S.H., Thermodynamic properties of cyclopropylamine,cyclopentylamine,and methylenecyclobutane, J. Chem. Thermodyn., 1981, 13, 345. [all data]

Lebedev, Tsvetkova, et al., 1978, 3
Lebedev, B.V.; Tsvetkova, L.Ya.; Rabinovich, I.B., Thermodynamics of methylenecyclobutane, J. Chem. Thermodyn., 1978, 10, 809-15. [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]

Lebedev, Tsvetkova, et al., 1978, 4
Lebedev, B.V.; Tsvetkova, L.Y.; Rabinovich, I.B.; Finkel'shtein, E.S.; Strel'chick, B.S., Termodin. Org. Soedin., 1978, 7, 3. [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]

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]

Puttemans and Delvaux, 1973
Puttemans, J.-P.; Delvaux, J.C., Ionisation et fragmentation d'isomeres C₅H₈ sous impact electronique. Spiropentane - methylenecyclobutane - isoprene, Ing. Chim. Brussell, 1973, 55(267-8), 7. [all data]

Demeo and Yencha, 1970
Demeo, D.A.; Yencha, A.J., Photoelectron spectra of bicyclic and exocyclic olefins, J. Chem. Phys., 1970, 53, 4536. [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]

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]

Guo and Kass, 1992
Guo, H.Z.; Kass, S.R., Vinylcyclopropyl Anion - Structure, Reactivity, Thermodynamic Properties, and an Unusual Rearrangement, J. Am. Chem. Soc., 1992, 114, 4, 1244, https://doi.org/10.1021/ja00030a019 . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,gas	Constant pressure heat capacity of gas
  Cp,liquid	Constant pressure heat capacity of liquid
  S°gas	Entropy of gas at standard conditions
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔHtrs	Enthalpy of phase transition
  ΔStrs	Entropy of phase transition
  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
  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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