Bicyclo[2.1.0]pentane

• Formula: C₅H₈
• Molecular weight: 68.1170
• IUPAC Standard InChI: InChI=1S/C5H8/c1-2-5-3-4(1)5/h4-5H,1-3H2 Copy

  
• IUPAC Standard InChIKey: MHLPKAGDPWUOOT-UHFFFAOYSA-N Copy
• CAS Registry Number: 185-94-4
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Information on this page:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Mass spectrum (electron ionization)
• Data at other public NIST sites:
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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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Reaction 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 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

 +  =

By formula: H₂ + C₅H₈ = C₅H₁₀

=  + 

By formula: C₅H₈N₂ = C₅H₈ + N₂

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 compiled by: Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

View reactions leading to C₅H₈⁺ (ion structure unspecified)

Ionization energy determinations

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry 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]

Roth, Klarner, et al., 1980
Roth, W.R.; Klarner, F.-G.; Lennartz, H.-W., Heats of hydrogenation. II. Heat of hydrogenation of bicyclo[2.1.0]pent-2-ene, an antiaromatic system, Chem. Ber., 1980, 113, 1806-1818. [all data]

Turner, Goebel, et al., 1968
Turner, R.B.; Goebel, P.; Mallon, B.J.; Doering, W.E.; Coburn, J.F., Jr.; Pomerantz, M., Heats of hydrogenation. VIII. Compounds with three- and four-membered rings, J. Am. Chem. Soc., 1968, 90, 4315-4322. [all data]

Herman and Goodman, 1989
Herman, M.S.; Goodman, J.L., Determination of the enthalpy and reaction volume changes of organic photoreactions using photoacoustic calorimetry, J. Am. Chem. Soc., 1989, 111, 1849-1854. [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]

Notes

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  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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