2-Butene, 2,3-dimethyl-

• Formula: C₆H₁₂
• Molecular weight: 84.1595
• IUPAC Standard InChI: InChI=1S/C6H12/c1-5(2)6(3)4/h1-4H3 Copy

  
• IUPAC Standard InChIKey: WGLLSSPDPJPLOR-UHFFFAOYSA-N Copy
• CAS Registry Number: 563-79-1
• 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: Tetramethylethylene; 1,1,2,2-Tetramethylethylene; 2,3-Dimethyl-2-butene; 2,3-Dimethylbut-2-ene; 2,3-Dimethylbutene-2; (CH3)2C=C(CH3)2; Tetramethylethene
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• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • IR Spectrum
  • UV/Visible spectrum
  • Gas Chromatography
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  • Gas Phase Kinetics Database
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Gas phase thermochemistry 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:
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

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:
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 C₆H₁₂⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

Mass spectrum (electron ionization)

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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

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry 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.

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]

Rodgers and Wu, 1971
Rodgers, A.S.; Wu, M.-C.R., Thermochemistry of the gas-phase iodine catalyzed isomerization: 2,3-dimethyl-1-butene = 2,3-dimethyl-2-butene, J. Chem. Thermodyn., 1971, 3, 591-597. [all data]

Scott D.W., 1955
Scott D.W., 2,3-Dimethyl-2-butene: thermodynamic properties in the solid, liquid and vapor states, J. Am. Chem. Soc., 1955, 77, 4993-4998. [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]

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]

Lossing and Traeger, 1975
Lossing, F.P.; Traeger, J.C., Stabilization in cyclopentadienyl, cyclopentenyl, and cyclopentyl cations, J. Am. Chem. Soc., 1975, 97, 1579. [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]

Frost and Sandhu, 1971
Frost, D.C.; Sandhu, J.S., Ionization potentials of ethylene and some methyl-substituted ethylenes as determined by photoelectron spectroscopy, Indian J. Chem., 1971, 9, 1105. [all data]

Bralsford, Harris, et al., 1960
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]

Kovac, Mohraz, et al., 1980
Kovac, B.; Mohraz, M.; Heilbronner, E.; Boekelheide, V.; Hopf, H., Photoelectron spectra of the cyclophanes, J. Am. Chem. Soc., 1980, 102, 4314. [all data]

McAlduff and Houk, 1977
McAlduff, E.J.; Houk, K.N., Photoelectron spectra of substituted oxiranes and thiiranes. Substituent effects on ionization potentials involving σ orbitals, Can. J. Chem., 1977, 55, 318. [all data]

Mollere, Houk, et al., 1976
Mollere, P.D.; Houk, K.N.; Bomse, D.S.; Morton, T.H., Photoelectron spectra of sterically congested alkenes and dienes, J. Am. Chem. Soc., 1976, 98, 4732. [all data]

Fuss and Bock, 1974
Fuss, W.; Bock, H., Photoelectron spectra and molecular properties. XXXVI. (H₃C)₃B, (H₃C)₂BF, (H₃C)₂BN(CH₃)₂, and (H₃C)₂CC(CH₃)₂: The use of ionization potentials in assigning UV spectra, J. Chem. Phys., 1974, 61, 1613. [all data]

Lossing and Traeger, 1975, 2
Lossing, F.P.; Traeger, J.C., Free radicals by mass spectrometry XLVI. Heats of formation of C₅H₇ and C₅H₉ radicals and cations., J. Am. Chem. Soc., 1975, 19, 9. [all data]

Notes

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

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,gas	Constant pressure heat capacity of gas
  IE (evaluated)	Recommended ionization energy
  ΔfH°gas	Enthalpy of formation of gas at standard conditions

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