2-Butene, 2,3-dimethyl-

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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

Quantity Value Units Method Reference Comment
Δfgas-16.80 ± 0.36kcal/molEqkWiberg and Hao, 1991Heat of hydration; ALS
Δfgas-16.35 ± 0.35kcal/molEqkRodgers and Wu, 1971Heat of isomerization; ALS

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
32.340 ± 0.065334.20Scott D.W., 1955GT
33.939 ± 0.067355.25
36.960 ± 0.074393.20
40.069 ± 0.081433.20
43.100 ± 0.086473.20

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
27.710273.15Scott D.W., 1955Recommended results of statistical thermodynamics calculation are in good agreement with experimental data.; GT
29.541298.15
29.680300.
37.481400.
45.041500.
51.781600.
57.670700.
62.780800.
67.249900.
71.1401000.
74.5511100.
77.5101200.
80.0791300.
82.3301400.
84.3091500.

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

Quantity Value Units Method Reference Comment
Δfliquid-24.60 ± 0.35kcal/molEqkWiberg and Hao, 1991Heat of hydration; ALS
Quantity Value Units Method Reference Comment
liquid64.579cal/mol*KN/AScott, Finke, et al., 1955DH
liquid65.11cal/mol*KN/AParks, Todd, et al., 1936Extrapolation below 90 K, 58.45 J/mol*K.; DH

Constant pressure heat capacity of liquid

Cp,liquid (cal/mol*K) Temperature (K) Reference Comment
41.750298.15Scott, Finke, et al., 1955T = 10 to 320 K.; DH
42.000295.5Parks, Todd, et al., 1936T = 83 to 296 K. Value is unsmoothed experimental datum.; DH

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

Quantity Value Units Method Reference Comment
Tboil346.3 ± 0.4KAVGN/AAverage of 28 out of 30 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus198.8 ± 0.3KAVGN/AAverage of 13 out of 15 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple198.92KN/AScott, Finke, et al., 1955, 2Crystal phase 1 phase; Uncertainty assigned by TRC = 0.01 K; TRC
Ttriple198.900KN/AWaddington, 1951Crystal phase 1 phase; Uncertainty assigned by TRC = 0.05 K; TRC
Ttriple198.920KN/AWaddington, 1951Crystal phase 1 phase; Uncertainty assigned by TRC = 0.02 K; TRC
Ttriple198.5KN/AParks, Todd, et al., 1936, 2Crystal phase 1 phase; Uncertainty assigned by TRC = 0.2 K; TRC
Quantity Value Units Method Reference Comment
Tc524.KN/AMajer and Svoboda, 1985 
Quantity Value Units Method Reference Comment
Δvap7.808kcal/molN/AMajer and Svoboda, 1985 
Δvap7.77kcal/molN/AReid, 1972AC
Δvap7.78kcal/molVCamin and Rossini, 1956ALS
Δvap7.79kcal/molN/ACamin and Rossini, 1956, 2Based on data from 289. to 347. K.; AC

Enthalpy of vaporization

ΔvapH (kcal/mol) Temperature (K) Method Reference Comment
7.084346.4N/AMajer and Svoboda, 1985 
7.67328.N/AUusi-Kyyny, Pokki, et al., 2004Based on data from 313. to 346. K.; AC
7.91297.AStephenson and Malanowski, 1987Based on data from 282. to 348. K. See also Bevan, Malkin, et al., 1955.; AC
7.82304.N/AFried, Baghdoyan, et al., 1971Based on data from 289. to 347. K.; AC
7.86 ± 0.02292.CScott, Finke, et al., 1955AC
7.65 ± 0.02308.CScott, Finke, et al., 1955AC
7.39 ± 0.02326.CScott, Finke, et al., 1955AC
7.10 ± 0.02346.CScott, Finke, et al., 1955AC

Enthalpy of vaporization

ΔvapH = A exp(-βTr) (1 − Tr)β
    ΔvapH = Enthalpy of vaporization (at saturation pressure) (kcal/mol)
    Tr = reduced temperature (T / Tc)

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Temperature (K) A (kcal/mol) β Tc (K) Reference Comment
292. to 346.11.540.2801524.Majer and Svoboda, 1985 

Antoine Equation Parameters

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

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Temperature (K) A B C Reference Comment
289.48 to 347.003.698971021.564-70.242Baghdoyan, Malik, et al., 1971Coefficents calculated by NIST from author's data.
302.18 to 346.364.090161224.926-46.812Scott, Finke, et al., 1955Coefficents calculated by NIST from author's data.

Enthalpy of fusion

ΔfusH (kcal/mol) Temperature (K) Reference Comment
1.54198.9Domalski and Hearing, 1996AC

Entropy of fusion

ΔfusS (cal/mol*K) Temperature (K) Reference Comment
4.288196.8Domalski and Hearing, 1996CAL
7.741198.9

Enthalpy of phase transition

ΔHtrs (kcal/mol) Temperature (K) Initial Phase Final Phase Reference Comment
0.8439196.82crystaline, IIcrystaline, IScott, Finke, et al., 1955DH
1.542198.92crystaline, IliquidScott, Finke, et al., 1955Enthalpies of transition and fusion calculated from total enthalpy change 196.82 to 198.92 K and assumed Cp of 150 J/mol*K for c,I.; DH
1.094196.6crystaline, IIcrystaline, IParks, Todd, et al., 1936DH
1.305198.5crystaline, IliquidParks, Todd, et al., 1936DH

Entropy of phase transition

ΔStrs (cal/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
4.288196.82crystaline, IIcrystaline, IScott, Finke, et al., 1955DH
7.753198.92crystaline, IliquidScott, Finke, et al., 1955Enthalpies; DH
5.564196.6crystaline, IIcrystaline, IParks, Todd, et al., 1936DH
6.575198.5crystaline, IliquidParks, Todd, et al., 1936DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, 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:
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)

Quantity Value Units Method Reference Comment
IE (evaluated)8.27 ± 0.01eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)194.5kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity187.8kcal/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
8.27 ± 0.02PEBieri, Burger, et al., 1977LLK
8.16EILossing and Traeger, 1975LLK
8.271 ± 0.005PEMasclet, Grosjean, et al., 1973LLK
8.26PEFrost and Sandhu, 1971LLK
8.30PIBralsford, Harris, et al., 1960RDSH
8.30PEKovac, Mohraz, et al., 1980Vertical value; LLK
10.52PEMcAlduff and Houk, 1977Vertical value; LLK
8.46PEMollere, Houk, et al., 1976Vertical value; LLK
8.42PEFuss and Bock, 1974Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C5H9+8.16CH3EILossing and Traeger, 1975, 2LLK
C5H9+10.32CH3EILossing and Traeger, 1975LLK

Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, 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

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Mass spectrum
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Additional Data

View image of digitized spectrum (can be printed in landscape orientation).

Due to licensing restrictions, this spectrum cannot be downloaded.

Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin Japan AIST/NIMC Database- Spectrum MS-NW-3539
NIST MS number 230825

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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