2,5-Norbornadiene

• Formula: C₇H₈
• Molecular weight: 92.1384
• IUPAC Standard InChI: InChI=1S/C7H8/c1-2-7-4-3-6(1)5-7/h1-4,6-7H,5H2 Copy

  
• IUPAC Standard InChIKey: SJYNFBVQFBRSIB-UHFFFAOYSA-N Copy
• CAS Registry Number: 121-46-0
• 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: Bicyclo[2.2.1]hepta-2,5-diene; Bicyclo[2.2.1]heptadiene; Norbornadiene; 3,6-Methano-1,4-cyclohexadiene; Dicycloheptadiene; Bicyclo[2.2.1]-2,5-heptadiene; NSC 13672; 8,9,10-trinorborna-2,5-diene
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • IR Spectrum
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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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 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

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, IR Spectrum, 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
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
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 C₇H₈⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₇H₇^- +  =

By formula: C₇H₇^- + H⁺ = C₇H₈

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• LIQUID; Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY; 4 cm^-1 resolution
• SOLUTION (10% IN CCl4 FOR 4000-1250 CM^-1, 10% IN CS2 FOR 1250-450 CM^-1) VS. SOLVENT; CARY 90 (GRATING); DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

• gas

References

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, IR Spectrum, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Walsh R., 1975
Walsh R., The enthalpy of formation of bicyclo[2.2.1]hepta-2,5-diene. Thermodynamic functions of bicyclo[2.2.1]heptane and bicyclo[2.2.1]hepta-2,5-diene, J. Chem. Thermodyn., 1975, 7, 149-154. [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]

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]

Ohno, Ishide, et al., 1985
Ohno, K.; Ishide, T.; Naitoh, Y.; Izumi, Y., Study of stereochemical properties of molecular orbitals by penning ionization electron spectroscopy, J. Am. Chem. Soc., 1985, 107, 8082. [all data]

Traeger and McLoughlin, 1978
Traeger, J.C.; McLoughlin, R.G., A photoionization study of the energetics of C₇H₇⁺ ion formed from C₇H₈ precursors, Int. J. Mass Spectrom. Ion Phys., 1978, 27, 319. [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]

Houk, Rondan, et al., 1983
Houk, K.N.; Rondan, N.G.; Paddon-Row, M.N.; Jefford, C.W.; Huy, P.T.; Burrow, P.D.; Jordan, K.D., Ionization potentials, electron affinities, and molecular orbitals of 2-substituted norbornadienes. Theory of 1,2 and homo-1,4 carbene cycloaddition selectivities, J. Am. Chem. Soc., 1983, 105, 5563. [all data]

Bieri, Asbrink, et al., 1982
Bieri, G.; Asbrink, L.; Von Niessen, W., 30.4-nm He(II) photoelectron spectra of organic molecules, J. Electron Spectrosc. Relat. Phenom., 1982, 27, 129. [all data]

Worley and Webb, 1980
Worley, S.D.; Webb, T.R., The electronic structure of transition-metal carbonyl complexes of norbornadiene and mesitylene, J. Organomet. Chem., 1980, 192, 139. [all data]

Worley, Webb, et al., 1979
Worley, S.D.; Webb, T.R.; Gibson, D.H.; Ong, T.-S., On the electronic structures of cyclobutadiene trimethylenemethane, J. Organomet. Chem., 1979, 168, 16. [all data]

Kobayashi, 1978
Kobayashi, T., A new rule for photoelectron angular distributions of molecules, Phys. Lett. A, 1978, 69, 31. [all data]

Cowling, Johnstone, et al., 1973
Cowling, S.A.; Johnstone, R.A.W.; Gorman, A.A.; Smith, P.G., Photoelectron spectrum of 5-methylenenorborn-2-ene and through-space interactions (homobutadiene conjugation), J. Chem. Soc., Chem. Commun., 1973, 627. [all data]

Palmer and Findlay, 1972
Palmer, M.H.; Findlay, R.H., Ab initio molecular orbital calculations, the electronic structure and electron spectrum of norbornadiene, Chem. Phys. Lett., 1972, 15, 416. [all data]

Heilbronner and Martin, 1972
Heilbronner, E.; Martin, H.D., The π-orbital sequence in norbornadiene and related hydrocarbons, Helv. Chim. Acta, 1972, 55, 1490. [all data]

Bischof, Heilbronner, et al., 1971
Bischof, P.; Heilbronner, E.; Prinzbach, H.; Martin, H.D., A photoelectron-spectroscopic investigation of the homoconjugative interaction between π- and Walsh-orbitals in endo- and exo- cyclopropano-norbornene, Helv. Chim. Acta, 1971, 54, 1072. [all data]

Dolejsek, Hanus, et al., 1962
Dolejsek, Z.; Hanus, V.; Prinzbach, H., Das massenspektrometrische Verhalten von Quadricyclen, Angew. Chem., 1962, 74, 902. [all data]

Meyerson, McCollum, et al., 1961
Meyerson, S.; McCollum, J.D.; Rylander, P.N., Organic ions in the gas phase. VIII. Bicycloheptadiene, J. Am. Chem. Soc., 1961, 83, 1401. [all data]

Lee and Squires, 1986
Lee, R.E.; Squires, R.R., Anionic homoaromaticity: A gas phase experimental study, J. Am. Chem. Soc., 1986, 105, 5078. [all data]

Wright and Beauchamp, 1981
Wright, C.A.; Beauchamp, J.L., Infrared spectra of gas phase ions and their use in elucidating reaction mechanisms. Identification of C₇H₇- structural isomers by multiphoton electron detachment using a low-powered laser, J. Am. Chem. Soc., 1981, 103, 6499. [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  Cp,gas	Constant pressure heat capacity of gas
  IE (evaluated)	Recommended ionization energy
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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