Isoprene

• Formula: C₅H₈
• Molecular weight: 68.1170
• IUPAC Standard InChI: InChI=1S/C5H8/c1-4-5(2)3/h4H,1-2H2,3H3 Copy

  
• IUPAC Standard InChIKey: RRHGJUQNOFWUDK-UHFFFAOYSA-N Copy
• CAS Registry Number: 78-79-5
• 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.
• Other names: 1,3-Butadiene, 2-methyl-; β-Methylbivinyl; Isopentadiene; 2-Methyl-1,3-butadiene; 2-Methylbutadiene; CH2=C(CH3)CH=CH2; 2-Methylbuta-1,3-diene; 3-Methyl-1,3-butadiene; NSC 9237
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• Information on this page:
  • Reaction thermochemistry data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • IR Spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Gas Phase Kinetics Database
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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 as indicated in comments:
B - John E. Bartmess
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
RCD - Robert C. Dunbar

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Individual Reactions

C₅H₇^- +  =

By formula: C₅H₇^- + H⁺ = C₅H₈

=  + 

By formula: C₁₁H₈N₄ = C₆N₄ + C₅H₈

 +  =

By formula: C₆N₄ + C₅H₈ = C₁₁H₈N₄

 +  = ( • )

By formula: Ag⁺ + C₅H₈ = (Ag⁺ • C₅H₈)

Mass spectrum (electron ionization)

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

Spectrum

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Additional Data

UV/Visible spectrum

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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: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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Additional Data

References

Go To: Top, Reaction thermochemistry data, Mass spectrum (electron ionization), UV/Visible spectrum, Notes

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

Bartmess and McIver Jr., 1979
Bartmess, J.E.; McIver Jr., The Gas Phase Acidity Scale in Gas Phase Ion Chemistry, Gas Phase Ion Chemistry, V. 2, M.T. Bowers, Ed., Academic Press, NY, 1979, Ch. 11, Elsevier, 1979. [all data]

Rogers, 1971
Rogers, F.E., Thermochemistry of the Diels-Alder reaction. I. Enthalpy of addition of isoprene to tetracyanoethylene, J. Phys. Chem., 1971, 75, 1734-1737. [all data]

Ho, Yang, et al., 1997
Ho, Y.-P.; Yang, Y.-C.; Klippenstein, S.J.; Dunbar, R.C., Binding Energies of Ag+ and Cd+ Complexes from Analysis of Radiative Association Kinetics, J. Phys. Chem. A, 1997, 101, 18, 3338, https://doi.org/10.1021/jp9637284 . [all data]

Fihtengolts, et al., 1969
Fihtengolts, V.S., et al., Atlas of UV Absorption Spectra of Substances Used in Synthetic Rubber Manufacture, 1969, 9. [all data]

Notes

Go To: Top, Reaction thermochemistry data, Mass spectrum (electron ionization), UV/Visible spectrum, References

• Symbols used in this document:
  

  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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