2-Methyl-1-butene

• Formula: C₅H₁₀
• Molecular weight: 70.1329
• IUPAC Standard InChI: InChI=1S/C5H10/c1-4-5(2)3/h2,4H2,1,3H3 Copy

  
• IUPAC Standard InChIKey: MHNNAWXXUZQSNM-UHFFFAOYSA-N Copy
• CAS Registry Number: 563-46-2
• 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-Butene, 2-methyl-; γ-Isoamylene; 1-Isoamylene; C2H5C(CH3)=CH2; 2-Methylbutene-1; Isopentene; UN 2371; UN 2459; 2-methylbut-1-ene
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • IR Spectrum
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Phase change data

Go To: Top, 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:
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)

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Antoine Equation Parameters

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

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Enthalpy of fusion

Entropy of fusion

Gas phase ion energetics data

Go To: Top, Phase change 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:
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

Mass spectrum (electron ionization)

Go To: Top, Phase change 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

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Additional Data

References

Go To: Top, Phase change 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.

Chao, Hall, et al., 1983
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
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]

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]

Chao, Hall, et al., 1983, 2
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, 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, 1519-1525. [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]

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]

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]

Demeo and El-Sayed, 1970
Demeo, D.A.; El-Sayed, M.A., Ionization potential and structure of olefins, J. Chem. Phys., 1970, 52, 2622. [all data]

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

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

Go To: Top, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.