1-Propene, 2-methyl-

• Formula: C₄H₈
• Molecular weight: 56.1063
• IUPAC Standard InChI: InChI=1S/C4H8/c1-4(2)3/h1H2,2-3H3 Copy

  
• IUPAC Standard InChIKey: VQTUBCCKSQIDNK-UHFFFAOYSA-N Copy
• CAS Registry Number: 115-11-7
• 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: Propene, 2-methyl-; γ-Butylene; Isobutene; Isobutylene; Isopropylidenemethylene; 1,1-Dimethylethylene; 2-Methyl-1-propene; 2-Methylpropene; iso-C4H8; Methylpropene; UN 1055; 1,1-Dimethylethene; 2-Methylpropylene
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Ion clustering data
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • Gas phase ion energetics data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Electron-Impact Ionization Cross Sections (on physics 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

Constant pressure heat capacity of gas

Condensed 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: Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

Ion clustering 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:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

C₃H₉Si⁺ +  = (C₃H₉Si⁺ • )

By formula: C₃H₉Si⁺ + C₄H₈ = (C₃H₉Si⁺ • C₄H₈)

 +  = ( • )

By formula: H₄N⁺ + C₄H₈ = (H₄N⁺ • C₄H₈)

 +  = ( • )

By formula: Li⁺ + C₄H₈ = (Li⁺ • C₄H₈)

 +  = ( • )

By formula: Na⁺ + C₄H₈ = (Na⁺ • C₄H₈)

Free energy of reaction

Vibrational and/or electronic energy levels

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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: Takehiko Shimanouchi

Symmetry:   C_2ν     Symmetry Number σ = 2

Source: Shimanouchi, 1972

Notes

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Ion clustering data, Vibrational and/or electronic energy levels, Notes

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

Prosen, Maron, et al., 1951
Prosen, E.J.; Maron, F.W.; Rossini, F.D., Heats of combustion, formation, and insomerization of ten C₄ hydrocarbons, J. Res. NBS, 1951, 46, 106-112. [all data]

Guinchant, 1918
Guinchant, M.J., Etude sur la fonction acide dans les derives metheniques et methiniques, Ann. Chem., 1918, 10, 30-84. [all data]

Stull D.R., 1969
Stull D.R., Jr., The Chemical Thermodynamics of Organic Compounds. Wiley, New York, 1969. [all data]

Todd S.S., 1936
Todd S.S., Thermal data on organic compounds. XV. Some heat capacity, entropy and free energy data for the isomeric butenes, J. Am. Chem. Soc., 1936, 58, 134-137. [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]

Kilpatrick J.E., 1946
Kilpatrick J.E., Heat content, free energy function, entropy, and heat capacity of ethylene, propylene, and the four butenes to 1500 K, J. Res. Nat. Bur. Stand, 1946, 37, 163-171. [all data]

East A.L.L., 1997
East A.L.L., Ab initio statistical thermodynamical models for the computation of third-law entropies, J. Chem. Phys., 1997, 106, 6655-6674. [all data]

Scott R.B., 1945
Scott R.B., Specific heats of gaseous 1,3-butadiene, isobutene, styrene, and ethylbenzene, J. Res. Nat. Bur. Stand., 1945, 34, 243-254. [all data]

Todd and Parks, 1936
Todd, S.S.; Parks, G.S., Thermal data on organic compounds. XV. Some heat capacity, entropy and free energy data for the isomeric butenes, J. Am. Chem. Soc., 1936, 58, 134-137. [all data]

Rabinovich and Lebedev, 1971
Rabinovich, I.B.; Lebedev, B.V., On the thermodynamic stability of polyisobutylene. Tr. Khim. Khim. Tekhnol., 1971, 194-196. [all data]

Li and Stone, 1989
Li, X.; Stone, J.A., Determination of the beta silicon effect from a mass spectrometric study of the association of trimethylsilylium ion with alkenes, J. Am. Chem. Soc., 1989, 111, 15, 5586, https://doi.org/10.1021/ja00197a013 . [all data]

Meot-Ner (Mautner) and Sieck, 1991
Meot-Ner (Mautner), M.; Sieck, L.W., Proton affinity ladders from variable-temperature equilibrium measurements. 1. A reevaluation of the upper proton affinity range, J. Am. Chem. Soc., 1991, 113, 12, 4448, https://doi.org/10.1021/ja00012a012 . [all data]

Meot-Ner (Mautner) and Sieck, 1990
Meot-Ner (Mautner), M.; Sieck, L.W., Ion Thermochemistry at High Temperatures. 1. Thermochemistry of the Ammonium Ion from Variable - Temperature Equilibrium Measurements. Proton Transfer, Association, and Decomposition Reactions in Ammonia, Isobutene, and t-Butylamine, J. Phys. Chem., 1990, 94, 19, 7730, https://doi.org/10.1021/j100382a076 . [all data]

Staley and Beauchamp, 1975
Staley, R.H.; Beauchamp, J.L., Intrinsic Acid - Base Properties of Molecules. Binding Energies of Li+ to pi - and n - Donor Bases, J. Am. Chem. Soc., 1975, 97, 20, 5920, https://doi.org/10.1021/ja00853a050 . [all data]

Dzidic and Kebarle, 1970
Dzidic, I.; Kebarle, P., Hydration of the Alkali Ions in the Gas Phase. Enthalpies and Entropies of Reactions M+(H2O)n-1 + H2O = M+(H2O)n, J. Phys. Chem., 1970, 74, 7, 1466, https://doi.org/10.1021/j100702a013 . [all data]

McMahon and Ohanessian, 2000
McMahon, T.B.; Ohanessian, G., An Experimental and Ab Initio Study of the Nature of the Binding in Gas-Phase Complexes of Sodium Ions, Chem. Eur. J., 2000, 6, 16, 2931, https://doi.org/10.1002/1521-3765(20000818)6:16<2931::AID-CHEM2931>3.0.CO;2-7 . [all data]

Shimanouchi, 1972
Shimanouchi, T., Tables of Molecular Vibrational Frequencies Consolidated Volume I, National Bureau of Standards, 1972, 1-160. [all data]

Notes

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• Symbols used in this document:
  

  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
  T	Temperature
  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
  ΔrS°	Entropy of reaction at standard conditions

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