2-Butene, 2-methyl-

• Formula: C₅H₁₀
• Molecular weight: 70.1329
• IUPAC Standard InChI: InChI=1S/C5H10/c1-4-5(2)3/h4H,1-3H3 Copy

  
• IUPAC Standard InChIKey: BKOOMYPCSUNDGP-UHFFFAOYSA-N Copy
• CAS Registry Number: 513-35-9
• 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: Trimethylethylene; β-Isoamylene; Amylene; 1,1,2-Trimethylethylene; 2-Methyl-2-butene; 3-Methyl-2-butene; (CH3)2C=CHCH3; 2-Methylbut-2-ene; n-Amylene; Ethylene, trimethyl-; UN 2460; 2-Methylbutene-2; NSC 74118; Isopentene
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Ion clustering data
  • References
  • Notes
• Other data available:
  • Henry's Law data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • Computational Chemistry Comparison and Benchmark Database
  • 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
DRB - Donald R. Burgess, Jr.
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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

Phase change 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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of vaporization

Enthalpy of vaporization

Δ_vapH = A exp(-βT_r) (1 − T_r)^β
    Δ_vapH = Enthalpy of vaporization (at saturation pressure) (kJ/mol)
    T_r = reduced temperature (T / T_c)

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Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

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Enthalpy of fusion

Entropy of fusion

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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

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

=

By formula: C₅H₁₀ = C₅H₁₀

C₃H₉Si⁺ +  = (C₃H₉Si⁺ • )

By formula: C₃H₉Si⁺ + C₅H₁₀ = (C₃H₉Si⁺ • C₅H₁₀)

 +  =

By formula: C₅H₁₀ + CH₄O = C₆H₁₄O

 +  =

By formula: C₅H₁₀ + HCl = C₅H₁₁Cl

 +  =

By formula: C₅H₁₀ + C₂H₆O = C₇H₁₆O

 +  =

By formula: C₅H₁₀ + C₂HF₃O₂ = C₇H₁₁F₃O₂

=

By formula: C₅H₁₀ = C₅H₁₀

=

By formula: C₅H₁₀ = C₅H₁₀

 +  =

By formula: C₅H₁₀ + Br₂ = C₅H₁₀Br₂

 +  =

By formula: H₂ + C₅H₁₀ = C₅H₁₂

 +  =

By formula: C₅H₁₀ + CH₄O = C₆H₁₄O

=  + 

By formula: C₇H₁₆O = C₅H₁₀ + C₂H₆O

Gas phase ion energetics 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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
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 C₅H₁₀⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

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

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⁺ + C₅H₁₀ = (C₃H₉Si⁺ • C₅H₁₀)

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Notes

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

Wiberg and Hao, 1991
Wiberg, K.B.; Hao, S., Enthalpies of hydration of alkenes. 4. Formation of acyclic tert-alcohols, J. Org. Chem., 1991, 56, 5108-5110. [all data]

Good and Smith, 1979
Good, W.D.; Smith, N.K., The enthalpies of combustion of the isomeric pentenes in the liquid state. A warning to combustion calorimetrists about sample drying, J. Chem. Thermodyn., 1979, 11, 111-118. [all data]

Scott D.W., 1949
Scott D.W., Thermodynamic properties of three isomeric pentenes, J. Am. Chem. Soc., 1949, 71, 2767-2773. [all data]

Chao, Hall, et al., 1983
Chao, J.; Hall, K.R.; Yao, J.M., Thermodynamic properties of simple alkenes, Thermochim. Acta, 1983, 64(3), 285-303. [all data]

Todd, Oliver, et al., 1947
Todd, S.S.; Oliver, G.D.; Huffman, H.M., The heat capacities, heats of fusion and entropies of the six pentenes, J. Am. Chem. Soc., 1947, 69, 1519-1525. [all data]

Parks and Huffman, 1930
Parks, G.S.; Huffman, H.M., Thermal data on organic compounds. IX. A study of the effect of unsaturation on the heat capacities, entropies and free energies of some hydrocarbons and other compounds, J. Am. Chem. Soc., 1930, 52, 4381-4391. [all data]

Chao, Hall, et al., 1983, 2
Chao, J.; Hall, K.R.; Yao, J.M., Thermodynamic Properties of Simple Alkenes, Thermochim. Acta, 1983, 64, 285. [all data]

Todd, Oliver, et al., 1947, 2
Todd, S.S.; Oliver, G.D.; Huffman, H.M., The heat capacities, heats of fusion and entropies of the six pentenes., J. Am. Chem. Soc., 1947, 69, 1519. [all data]

Huffman, 1945
Huffman, H.M., Personal Commun., U. S. Bur. Mines, Bartlesville, OK, July 25, 1945. [all data]

Parks and Huffman, 1930, 2
Parks, G.S.; Huffman, H.M., Thermal data on organic compounds. IX. A study of the effect of unsaturation on the heat capacities, entropies and free energies of some hydrocarbons and other compounds, J. Am. Chem. Soc., 1930, 52, 4381. [all data]

Tsonopoulos and Ambrose, 1996
Tsonopoulos, C.; Ambrose, D., Vapor-Liquid Critical Properties of Elements and Compounds. 6. Unsaturated Aliphatic Hydrocarbons, J. Chem. Eng. Data, 1996, 41, 645-656. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

Reid, 1972
Reid, Robert C., Handbook on vapor pressure and heats of vaporization of hydrocarbons and related compounds, R. C. Wilhort and B. J. Zwolinski, Texas A Research Foundation. College Station, Texas(1971). 329 pages.$10.00, AIChE J., 1972, 18, 6, 1278-1278, https://doi.org/10.1002/aic.690180637 . [all data]

Scott, Waddington, et al., 1949
Scott, D.W.; Waddington, G.; Smith, J.C.; Huffman, H.M., Thermodynamic properties of three isomeric pentenes, J. Am. Chem. Soc., 1949, 71, 2767-2773. [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [all data]

Rihko, Linnekoski, et al., 1994
Rihko, L.K.; Linnekoski, J.A.; Krause, A.O., Reaction equilibria in the synthesis of 2-methoxy-2-methylbutane and 2-ethyoxy-2-methylbutane in the liquid phase, J. Chem. Eng. Data, 1994, 39, 700-704. [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]

Serda, Izquierdo, et al., 1995
Serda, J.A.; Izquierdo, J.F.; Tejero, J.; Cunill, F.; Iborra, M., Equilibrium and thermodynamics for 2-methyl-2-methoxybutane liquid-phase decomposition, Thermochim. Acta, 1995, 259, 111-120. [all data]

Arnett and Pienta, 1980
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]

Radyuk, Kabo, et al., 1973
Radyuk, Z.A.; Kabo, G.Ya.; Andreevskii, D.N., Isomerization equilibrium and thermodynamic properties of methylbutenes, Neftekhimiya, 1973, 13, 356-360. [all data]

Conn, Kistiakowsky, et al., 1938
Conn, J.B.; Kistiakowsky, G.B.; Smith, E.A., Heats of organic reactions. VII. Addition of halogens to olefins, J. Am. Chem. Soc., 1938, 60, 2764-2771. [all data]

Kistiakowsky, Ruhoff, et al., 1936
Kistiakowsky, G.B.; Ruhoff, J.R.; Smith, H.A.; Vaughan, W.E., Heats of organic reactions. III. Hydrogenation of some higher olefins, J. Am. Chem. Soc., 1936, 58, 137-145. [all data]

Sharonov, Rozhnov, et al., 1995
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]

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]

Traeger, 1986
Traeger, J.C., Heat of formation for the 1-methylallyl cation by photoionization mass spectrometry, J. Phys. Chem., 1986, 90, 4114. [all data]

Bieri, Burger, et al., 1977
Bieri, G.; Burger, F.; Heilbronner, E.; Maier, J.P., Valence ionization enrgies of hydrocarbons, Helv. Chim. Acta, 1977, 60, 2213. [all data]

Masclet, Grosjean, et al., 1973
Masclet, P.; Grosjean, D.; Mouvier, G., Alkene ionization potentials. Part I. Quantitative determination of alkyl group structural effects, J. Electron Spectrosc. Relat. Phenom., 1973, 2, 225. [all data]

Lossing, 1972
Lossing, F.P., Free radicals by mass spectrometry. XLV. Ionization potentials and heats of formation of C₃H₃, C₃H₅, and C₄H₇ radicals and ions, Can. J. Chem., 1972, 50, 3973. [all data]

Gross and Wilkins, 1971
Gross, M.L.; Wilkins, C.L., Computer-assisted ion cyclotron resonance appearance potential measurements for C₅H₁₀ isomers, Anal. Chem., 1971, 43, 1624. [all data]

Frost and Sandhu, 1971
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Bock and Seidl, 1968
Bock, H.; Seidl, H., d-Orbitaleffekte in siliziumsubstituierten π-Elektronensystemen. VI. Spektroskopische Untersuchungen an Alkyl- und Silylathylenen, J. Organometal. Chem., 1968, 13, 87. [all data]

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Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

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Bralsford, R.; Harris, P.V.; Price, W.C., The effect of fluorine on the electronic spectra and ionization potentials of molecules, Proc. Roy. Soc. (London), 1960, A258, 459. [all data]

Brand and Baer, 1984
Brand, W.A.; Baer, T., Dissociation dynamics of energy-selected C₅H₁₀⁺ ions, J. Am. Chem. Soc., 1984, 106, 3154. [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  Cp,gas	Constant pressure heat capacity of gas
  Cp,liquid	Constant pressure heat capacity of liquid
  IE (evaluated)	Recommended ionization energy
  Pc	Critical pressure
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

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