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
  The 3d structure may be viewed using Java or Javascript.
• 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
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Reaction thermochemistry data
  • Henry's Law data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Ion clustering data
  • IR Spectrum
  • UV/Visible spectrum
  • Vibrational and/or electronic energy levels
  • 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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Reaction thermochemistry data

Go To: Top, Henry's Law data, Gas phase ion energetics data, Mass spectrum (electron ionization), References, Notes

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
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
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

C₄H₇^- +  =

By formula: C₄H₇^- + H⁺ = C₄H₈

 +  = ( • )

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

=  + 

By formula: C₄H₉Cl = C₄H₈ + HCl

 +  =

By formula: C₄H₈ + C₂H₆O = C₆H₁₄O

C₃H₉Si⁺ +  = (C₃H₉Si⁺ • )

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

 +  =

By formula: C₄H₈ + H₂ = C₄H₁₀

=  + 

By formula: C₄H₉I = HI + C₄H₈

 +  =

By formula: C₄H₈ + C₃H₈O = C₇H₁₆O

 +  = ( • )

By formula: Li⁺ + C₄H₈ = (Li⁺ • C₄H₈)

 +  =

By formula: C₄H₈ + HCl = C₄H₉Cl

 +  =

By formula: C₄H₈ + H₂O = C₄H₁₀O

 +  = ( • )

By formula: Na⁺ + C₄H₈ = (Na⁺ • C₄H₈)

Free energy of reaction

(CAS Reg. No. 38130-30-2 • 4294967295) +  = CAS Reg. No. 38130-30-2

By formula: (CAS Reg. No. 38130-30-2 • 4294967295C₄H₈) + C₄H₈ = CAS Reg. No. 38130-30-2

( • 4294967295) +  =

By formula: (C₄H₉ • 4294967295C₄H₈) + C₄H₈ = C₄H₉

=  + 

By formula: C₅H₁₂O = C₄H₈ + CH₄O

=  + 

By formula: C₄H₈Br₂ = C₄H₈ + Br₂

 +  =

By formula: C₄H₈ + C₄H₁₀O = C₈H₁₈O

 +  =

By formula: C₄H₈ + C₄H₁₀O = C₈H₁₈O

 +  =

By formula: C₄H₈ + C₄H₁₀O = C₈H₁₈O

=  + 

By formula: C₆H₁₄O = C₄H₈ + C₂H₆O

=  + 

By formula: C₄H₉Br = C₄H₈ + HCl

 +  =

By formula: HBr + C₄H₈ = C₄H₉Br

 +  =

By formula: C₄H₈ + CH₄O = C₅H₁₂O

=  + 

By formula: C₄H₁₀O = C₄H₈ + H₂O

 +  =

By formula: C₇H₈O + C₄H₈ = C₁₁H₁₆O

=  + 

By formula: C₁₀H₁₄O = C₆H₆O + C₄H₈

Henry's Law 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: Rolf Sander

Henry's Law constant (water solution)

k_H(T) = k°_H exp(d(ln(k_H))/d(1/T) ((1/T) - 1/(298.15 K)))
k°_H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(k_H))/d(1/T) = Temperature dependence constant (K)

Gas phase ion energetics data

Go To: Top, Reaction thermochemistry data, Henry's Law data, Mass spectrum (electron ionization), 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
MM - Michael M. Meot-Ner (Mautner)
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 C₄H₈⁺ (ion structure unspecified)

Proton affinity at 298K

Gas basicity at 298K

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₄H₇^- +  =

By formula: C₄H₇^- + H⁺ = C₄H₈

Mass spectrum (electron ionization)

Go To: Top, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, References, Notes

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

References

Go To: Top, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, Mass spectrum (electron ionization), Notes

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

Wenthold, Hu, et al., 1999
Wenthold, P.G.; Hu, J.; Squires, R.R.; Lineberger, W.C., Photoelectron spectroscopy of the trimethylenemethane negative ion, J. Am. Soc. Mass Spectrom., 1999, 10, 9, 800-809, https://doi.org/10.1016/S1044-0305(99)00043-4 . [all data]

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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]

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Howlett, K.E., The use of equilibrium constants to calculate thermodynamic quantities. Part II, J. Chem. Soc., 1955, 1784-17. [all data]

Howlett, 1951
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Sola, L.; Pericas, M.A.; Cunill, F.; Tejero, J., Thermodynamic and kinetic studies of the liquid phase synthesis of tert-butyl ethyl ether using a reaction calorimeter, Ind. Eng. Chem. Res., 1995, 34, 3718-3725. [all data]

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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]

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Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

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Jones, J.L.; Ogg, R.A., Jr., The equilibrium (CH₃)₃CI = (CH₃)₂C = CH₂ + HI, J. Am. Chem. Soc., 1937, 59, 1943-1945. [all data]

Calderon, Tejero, et al., 1997
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Sola, L.; Pericas, M.A.; Cunill, F.; Izquierdo, J.F., A comparative thermodynamic and kinetic study of the reaction between olefins and light alcohols leading to branced ethers. Reaction calorimetry study of the formation of tert-amyl methyl ether (TAME) and tert-butyl isopropyl ether (IPTBE), Ind. Eng. Chem. Res., 1997, 36, 2012-2018. [all data]

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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]

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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]

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Arnett, E.M.; Pienta, N.J., Stabilities of carbonium ions in solution. 12. Heats of formation of alkyl chlorides as an entree to heats of solvation of aliphatic carbonium ions, J. Am. Chem. Soc., 1980, 102, 3329-3334. [all data]

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Eberz, W.F.; Lucas, H.J., The hydration of unsaturated compounds. II. The equilibrium between i-butene and t-butanol and the free energy of hydration of i-butene, J. Am. Chem. Soc., 1934, 56, 1230-1234. [all data]

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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]

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DePuy, C.H.; Gronert, S.; Barlow, S.E.; Bierbaum, V.M.; Damrauer, R., The Gas Phase Acidities of the Alkanes, J. Am. Chem. Soc., 1989, 111, 6, 1968, https://doi.org/10.1021/ja00188a003 . [all data]

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Arntz, H.; Gottlieb, K., High-pressure heat-flow calorimeter determination of the enthalpy of reaction for the synthesis of methyl t-butyl ether from methanol and 2-methylpropene, J. Chem. Thermodyn., 1985, 17, 967-972. [all data]

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Sharonov, Mishentseva, et al., 1991
Sharonov, K.G.; Mishentseva, Y.B.; Rozhnov, A.M.; Miroshnichenko, E.A.; Korchatova, L.I., Molar enthalpies of formation and vaporizqation of t-butoxybutanes and thermodynamics of their synthesis from a butanol and 2-methylpropene I. Equilibria of synthesis reactions of t-butoxybutanes in the liquid phase, J. Chem. Thermodyn., 1991, 23, 141-145. [all data]

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Sharonov, K.G.; Rozhnov, A.M.; Korol'kov, A.V.; Karaseva, S.Y., Enthalpies of formation of 2-methyl-2-ethoxypropane and 2-ethyl-2-ethoxypropane from equilibrium measurements, J. Chem. Thermodyn., 1995, 27, 751-753. [all data]

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Notes

Go To: Top, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  T	Temperature
  d(ln(kH))/d(1/T)	Temperature dependence parameter for Henry's Law constant
  k°H	Henry's Law constant at 298.15K
  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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