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
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• 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
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • IR Spectrum
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • 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

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

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

C₅H₇^- +  =

By formula: C₅H₇^- + H⁺ = C₅H₈

=  + 

By formula: C₁₁H₈N₄ = C₆N₄ + C₅H₈

 +  =

By formula: C₆N₄ + C₅H₈ = C₁₁H₈N₄

 +  = ( • )

By formula: Ag⁺ + C₅H₈ = (Ag⁺ • C₅H₈)

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

Gas Phase Spectrum

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Additional Data

Gas Chromatography

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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

Kovats' RI, non-polar column, isothermal

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Kovats' RI, non-polar column, custom temperature program

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Kovats' RI, polar column, isothermal

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Van Den Dool and Kratz RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, isothermal

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Normal alkane RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, custom temperature program

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Normal alkane RI, polar column, custom temperature program

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References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, IR Spectrum, Gas Chromatography, Notes

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

Fraser and Prosen, 1955
Fraser, F.M.; Prosen, E.J., Heats of combustion and isomerization of six pentadienes and spiropentane, J. Res. NBS, 1955, 54, 143-148. [all data]

Messerly J.F., 1970
Messerly J.F., Chemical thermodynamic properties of the pentadienes. Third law studies, J. Chem. Eng. Data, 1970, 15, 227-232. [all data]

Thermodynamics Research Center, 1997
Thermodynamics Research Center, Selected Values of Properties of Chemical Compounds., Thermodynamics Research Center, Texas A&M University, College Station, Texas, 1997. [all data]

Compton D.A.C., 1977
Compton D.A.C., Conformations of conjugated hydrocarbons. Part 2. A spectroscopic and thermodynamic study of cis- and trans-penta-1,3-diene, J. Chem. Soc. Perkin Trans. 2, 1977, 1311-1315. [all data]

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]

Heberger, 1990
Heberger, K., Identification of C₅H₈ Isomers Through Reactions of Singlet Methylene, CH₂(ã¹A₁), with Unsaturated Hydrocarbons Using Capillary Gas Chromatography - Mass Spectrometry, Analyst, 1990, 115, 6, 725-729, https://doi.org/10.1039/an9901500725 . [all data]

Safina, Poznyak, et al., 1989
Safina, L.R.; Poznyak, T.I.; Lisitsyn, D.M.; Kiseleva, E.V.; Kovalev, G.I., Selective gas-chromatographic determination of trace unsaturated and aromatic-hydrocarbons in complex-mixtures, J. Appl. Chem. USSR (Engl. Transl.), 1989, 44, 5, 749-754. [all data]

Papazova, Milina, et al., 1988
Papazova, D.; Milina, R.; Dimov, N., Comparative evaluation of retention of hydrocarbons present in the C₅-petroleum fraction of methylsilicone and squalane phases, Chromatographia, 1988, 25, 3, 177-180, https://doi.org/10.1007/BF02316441 . [all data]

Bredael, 1982
Bredael, P., Retention indices of hydrocarbons on SE-30, J. Hi. Res. Chromatogr. Chromatogr. Comm., 1982, 5, 6, 325-328, https://doi.org/10.1002/jhrc.1240050610 . [all data]

Bajus, Veselý, et al., 1979
Bajus, M.; Veselý, V.; Leclercq, P.A.; Rijks, J.A., Steam cracking of hydrocarbons. 2. Pyrolysis of methylcyclohexane, Ind. Eng. Chem. Prod. Res. Dev., 1979, 18, 2, 135-142, https://doi.org/10.1021/i360070a012 . [all data]

Schomburg and Dielmann, 1973
Schomburg, G.; Dielmann, G., Identification by means of retention parameters, J. Chromatogr. Sci., 1973, 11, 3, 151-159, https://doi.org/10.1093/chromsci/11.3.151 . [all data]

Hively and Hinton, 1968
Hively, R.A.; Hinton, R.E., Variation of the retention index with temperature on squalane substrates, J. Gas Chromatogr., 1968, 6, 4, 203-217, https://doi.org/10.1093/chromsci/6.4.203 . [all data]

Widmer, 1967
Widmer, H., Gas chromatographic identification of hydrocarbons using retention indices, J. Gas Chromatogr., 1967, 5, 10, 506-510, https://doi.org/10.1093/chromsci/5.10.506 . [all data]

Zulaïca and Guiochon, 1966
Zulaïca, J.; Guiochon, G., Analyse des hauts polymères par chromatographie en phase gazeuse de leurs produits de pyrolyse. II. Application à quelques hydrocarbures macromoléculaires purs, Bull. Soc. Chim. Fr., 1966, 4, 1351-1363. [all data]

Wehrli and Kováts, 1959
Wehrli, A.; Kováts, E., Gas-chromatographische Charakterisierung ogranischer Verbindungen. Teil 3: Berechnung der Retentionsindices aliphatischer, alicyclischer und aromatischer Verbindungen, Helv. Chim. Acta, 1959, 7, 7, 2709-2736, https://doi.org/10.1002/hlca.19590420745 . [all data]

Haagen-Smit Laboratory, 1997
Haagen-Smit Laboratory, Procedure for the detailed hydrocarbon analysis of gasolines by single column high efficiency (capillary) column gas chromatography, SOP NO. MLD 118, Revision No. 1.1, California Environmental Protection Agency, Air Resources Board, El Monte, California, 1997, 22. [all data]

Hoekman, 1993
Hoekman, S.K., Improved gas chromatography procedure for speciated hydrocarbon measurements of vehicle emissions, J. Chromatogr., 1993, 639, 2, 239-253, https://doi.org/10.1016/0021-9673(93)80260-F . [all data]

Helmig, Klinger, et al., 1999
Helmig, D.; Klinger, L.F.; Guenther, A.; Vierling, L.; Geron, C.; Zimmerman, P., Biogenic volatile organic compound emissions (BVOCs). I. Identifications from three continental sites in the U.S., Chemosphere, 1999, 38, 9, 2163-2187, https://doi.org/10.1016/S0045-6535(98)00425-1 . [all data]

Helmig, Pollock, et al., 1996
Helmig, D.; Pollock, W.; Greenberg, J.; Zimmerman, P., Gas chromatography mass spectrometry analysis of volatile organic trace gases at Mauna Loa Observatory, Hawaii, J. Geophys. Res., 1996, 101, D9, 14697-14710, https://doi.org/10.1029/96JD00212 . [all data]

Schomburg, 1966
Schomburg, G., Gaschromatographische Retentionsdaten und Struktur Chemischer Verbindungen. II. Methylverzweigungen und Doppelbindungen in Offenkettigen Kohlenwasserstoffen, J. Chromatogr., 1966, 23, 1-17, https://doi.org/10.1016/S0021-9673(01)98652-2 . [all data]

Bramston-Cook, 2013
Bramston-Cook, R., Kovats indices for C2-C13 hydrocarbons and selected oxygenated/halocarbons with 100 % dimethylpolysiloxane columns, 2013, retrieved from http://lotusinstruments.com/monographs/List .... [all data]

Supelco, 2012
Supelco, CatalogNo. 24160-U, Petrocol DH Columns. Catalog No. 24160-U, 2012, retrieved from http://www.sigmaaldrich.com/etc/medialib/docs/Supelco/Datasheet/1/w97949.Par.0001.File.tmp/w97949.pdf. [all data]

Baraldi, Rapparini, et al., 1999
Baraldi, R.; Rapparini, F.; Rossi, F.; Latella, A.; Ciccioli, P., Volatile organic compound emissions from flowers of the most occurring and economically important species of fruit trees, Phys. Chem. Earth, 1999, 24, 6, 729-732, https://doi.org/10.1016/S1464-1909(99)00073-8 . [all data]

Orav, Kailas, et al., 1999
Orav, A.; Kailas, T.; Muurisepp, M.; Kann, J., Composition of the oil from waste tires. 1. Fraction boiling at yp to 160 0C, Proc. Estonian Acad. Sci. Chem., 1999, 48, 1, 30-39. [all data]

Chupalov and Zenkevich, 1996
Chupalov, A.A.; Zenkevich, I.G., Chromatographic Characterization of Structural Transformations of Organic Compounds in Diels-Alder Reaction. Aliphatic Dienes and Dienophyls, Zh. Org. Khim., 1996, 32, 6, 675-684. [all data]

Ciccioli, Cecinato, et al., 1992
Ciccioli, P.; Cecinato, A.; Brancaleoni, E.; Frattoni, M.; Liberti, A., Use of carbon adsorption traps combined with high resolution gas chromatography - mass spectrometry for the analysis of polar and non-polar C₄-C₁₄ hydrocarbons involved in photochemical smog formation, J. Hi. Res. Chromatogr., 1992, 15, 2, 75-84, https://doi.org/10.1002/jhrc.1240150205 . [all data]

Blunden, Aneja, et al., 2005
Blunden, J.; Aneja, V.P.; Lonneman, W.A., Characterization of non-methane volatile organic compounds at swine facilities in eastern North Carolina, Atm. Environ., 2005, 39, 36, 6707-6718, https://doi.org/10.1016/j.atmosenv.2005.03.053 . [all data]

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Zenkevich, I.G., Application of Methods of Molecular Dynamics in Chromato-Spectral Identification of ISomeric Products of Organic reactions (in Russian), Zh. Org. Khim., 1998, 34, 10, 1463-1470. [all data]

Flanagan, Streete, et al., 1997
Flanagan, R.J.; Streete, P.J.; Ramsey, J.D., Volatile Substance Abuse, UNODC Technical Series, No 5, United Nations, Office on Drugs and Crime, Vienna International Centre, PO Box 500, A-1400 Vienna, Austria, 1997, 56, retrieved from http://www.odccp.org/pdf/technical_series₁997-01-01₁.pdf. [all data]

Ciccioli, Cecinato, et al., 1994
Ciccioli, P.; Cecinato, A.; Brancaleoni, E.; Brachetti, A.; Frattoni, M.; Sparapani, R., Composition and Distribution of Polar and Non-Polar VOCs in Urban, Rural, Forest and Remote Areas, Eur Commission EUR, 1994, 549-568. [all data]

Ciccioli, Brancaleoni, et al., 1993
Ciccioli, P.; Brancaleoni, E.; Cecinato, A.; Sparapani, R.; Frattoni, M., Identification and determination of biogenic and anthropogenic volatile organic compounds in forest areas of Northern and Southern Europe and a remote site of the Himalaya region by high-resolution gas chromatography-mass spectrometry, J. Chromatogr., 1993, 643, 1-2, 55-69, https://doi.org/10.1016/0021-9673(93)80541-F . [all data]

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Strete, P.J.; Ruprah, M.; Ramsey, J.D.; Flanagan, R.J., Detection and identification of volatile substances by headspace capillary gas chromatography to aid the diagnosis of acute poisoning, Analyst, 1992, 117, 7, 1111-1127, https://doi.org/10.1039/an9921701111 . [all data]

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Waggott, A.; Davies, I.W., Identification of organic pollutants using linear temperature programmed retention indices (LTPRIs) - Part II, 1984, retrieved from http://dwi.defra.gov.uk/research/completed-research/reports/dwi0383.pdf. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, IR Spectrum, Gas Chromatography, References

• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  S°gas	Entropy of gas at standard conditions
  ΔcH°gas	Enthalpy of combustion of gas at standard conditions
  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

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