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
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• 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
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
  • IR Spectrum
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • 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 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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
CAL - James S. Chickos, William E. Acree, Jr., Joel F. Liebman, Students of Chem 202 (Introduction to the Literature of Chemistry), University of Missouri -- St. Louis
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) (kcal/mol)
    T_r = reduced temperature (T / T_c)

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Antoine Equation Parameters

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

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Enthalpy of fusion

Entropy of fusion

Enthalpy of phase transition

Entropy of phase transition

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, Condensed phase thermochemistry data, 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.

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]

Scott, Finke, et al., 1955
Scott, D.W.; Finke, H.L.; McCullough, J.P.; Gross, M.E.; Messerly, J.F.; Pennington, R.E.; Waddington, G., 2,3-Dimethyl-2-butene: Thermodynamic properties in the solid, liquid and vapor states, J. Am. Chem. Soc., 1955, 77, 4993-4998. [all data]

Parks, Todd, et al., 1936
Parks, G.S.; Todd, S.S.; Shomate, C.H., Thermal data on organic compounds. XVII. Some heat capacity, entropy and free energy data for five higher olefins, J. Am. Chem. Soc., 1936, 58, 2505-2508. [all data]

Scott, Finke, et al., 1955, 2
Scott, D.W.; Finke, H.L.; McCullough, J.P.; Gross, M.E.; Messerly, J.F.; Pennington, R.E.; Waddington, G., 2,3-dimethyl-2-butene: thermodynamic properties in the solid, liquid, and vapor states., J. Am. Chem. Soc., 1955, 77, 4993. [all data]

Waddington, 1951
Waddington, G., Personal Commun., U. S. Bur. Mines, Bartlesville, OK, 1951. [all data]

Parks, Todd, et al., 1936, 2
Parks, G.S.; Todd, S.S.; Shomate, C.H., Thermal data on organic compounds. XVII. Some heat capacity, entropy and free energy data for five higher olefins, J. Am. Chem. Soc., 1936, 58, 2505. [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]

Camin and Rossini, 1956
Camin, D.L.; Rossini, F.D., Physical properties of the 17 isomeric hexenes of the API research series, J. Phys. Chem., 1956, 60, 1446. [all data]

Camin and Rossini, 1956, 2
Camin, David L.; Rossini, Frederick D., Physical Properties of the 17 Isomeric Hexenes.of the API Research Series, J. Phys. Chem., 1956, 60, 10, 1446-1451, https://doi.org/10.1021/j150544a029 . [all data]

Uusi-Kyyny, Pokki, et al., 2004
Uusi-Kyyny, Petri; Pokki, Juha-Pekka; Kim, Younghun; Aittamaa, Juhani, Isobaric Vapor Liquid Equilibrium for 2,3-Dimethyl-2-butene + Methanol, + Ethanol, + 2-Propanol, or + 2-Butanol at Atmospheric Pressure, J. Chem. Eng. Data, 2004, 49, 2, 251-255, https://doi.org/10.1021/je034106w . [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]

Bevan, Malkin, et al., 1955
Bevan, T.H.; Malkin, T.; Smith, D.B.; Davey, W.; Gwilt, J.R.; Cooper, W.; Kertes, S.; Roberts, J.J.; Ross, W.C.J.; Wilson, Walter; Cummings, G.A.McD.; McLaughlin, E., Notes, J. Chem. Soc., 1955, 1383, https://doi.org/10.1039/jr9550001383 . [all data]

Fried, Baghdoyan, et al., 1971
Fried, Vojtech.; Baghdoyan, Armen.; Malik, Jana., Vapor pressures and densities of 2,3-dimethyl-2-butene and 3,3-dimethyl-1-butene, J. Chem. Eng. Data, 1971, 16, 1, 96-97, https://doi.org/10.1021/je60048a009 . [all data]

Baghdoyan, Malik, et al., 1971
Baghdoyan, A.; Malik, J.; Fried, V., Vapor Pressures and Densities of 2,3-Dimethyl-2-butene and 3,3-Dimethyl-1-butene, J. Chem. Eng. Data, 1971, 16, 1, 96-97, https://doi.org/10.1021/je60048a009 . [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]

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, Condensed phase thermochemistry data, Phase change 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
  Cp,liquid	Constant pressure heat capacity of liquid
  IE (evaluated)	Recommended ionization energy
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔHtrs	Enthalpy of phase transition
  ΔStrs	Entropy of phase transition
  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
  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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