α-Methylstyrene

• Formula: C₉H₁₀
• Molecular weight: 118.1757
• IUPAC Standard InChI: InChI=1S/C9H10/c1-8(2)9-6-4-3-5-7-9/h3-7H,1H2,2H3 Copy

  
• IUPAC Standard InChIKey: XYLMUPLGERFSHI-UHFFFAOYSA-N Copy
• CAS Registry Number: 98-83-9
• 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: Benzene, (1-methylethenyl)-; Styrene, α-methyl-; α-Methylstyrol; β-Phenylpropylene; Isopropenylbenzene; 1-Methyl-1-phenylethylene; 1-Phenyl-1-methylethylene; 1-Propene, 2-phenyl-; 2-Phenyl-1-propene; 2-Phenylpropene; (1-Methylethenyl)benzene; AS-Methylphenylethylene; β-phenylpropene; α-Methylstyreen; α-Metil-stirolo; Isopropenil-benzolo; Isopropenyl-benzeen; Isopropenyl-benzol; 2-Phenylpropylene; UN 2303; Benzene, isopropenyl-; 2-Phenyl-2-propene; 1-Methyl-1-phenylethene; NSC 9400; a-methylstyrene
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • 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

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

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

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

Gas phase ion energetics data

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

Data compiled as indicated in comments:
B - John E. Bartmess
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 C₉H₁₀⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₉H₉^- +  =

By formula: C₉H₉^- + H⁺ = C₉H₁₀

References

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

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

Guthrie, 1978
Guthrie, J.P., Equilibrium constants for a series of simple aldol condensations, and linear free energy relations with other carbonyl addition reactions, Can. J. Chem., 1978, 56, 962-973. [all data]

Krall and Roberts, 1958
Krall, R.E.; Roberts, J.D., Strain variation in the unsaturated cyclobutane ring, Am. Chem. Soc. Div. Pet. Chem., 1958, 3, 63-68. [all data]

Thermodynamics Research Center, 1997
Thermodynamics Research Center, Selected Values of Properties of Chemical Compounds., Thermodynamics Research Center, Texas A&M University, College Station, Texas, 1997. [all data]

Roberts and Jessup, 1951
Roberts, D.E.; Jessup, R.S., Heat of polymerization of alpha-methylstyrene from heats of combustion of monomer and four polymer fractions, J. Res. NBS, 1951, 46, 11-17. [all data]

Lemoult, 1911
Lemoult, M.P., Thermochimie. - Recherches sur les derives du styrolene; rectification de quelques erreurs experimentales, Compt. Rend., 1911, 152, 1402-1404. [all data]

Auwsers, Roth, et al., 1910
Auwsers, K.; Roth, W.A.; Eisenlohr, F., III. Verbrennungswarmen von Terpenen und Styrolen, Justus Liebigs Ann. Chem., 1910, 267-290. [all data]

Lebedev and Rabinovich, 1971
Lebedev, B.V.; Rabinovich, I.B., Heat capacities and thermodynamic functions of a-methylstyrene and poly(a-methylstyrene), Tr. Khim. Khim. Tekhnol., 1971, 1, 12-15. [all data]

Anonymous, 1952
Anonymous, R., , Physical Properties of Chemical Substances, Dow Chemical Co., 1952. [all data]

Anonymous, 1946
Anonymous, R., , Am. Pet. Inst. Res. Proj. 45, Ohio State Univ., 1946. [all data]

Stull, 1945
Stull, D.R., Personal Commun., Dow Chemical Co., 1945. [all data]

Anonymous, 1943
Anonymous, R., , Sunbury Rep. No. 2176, Anglo-Iranian Oil Co., 1943. [all data]

Steele, Chirico, et al., 1997
Steele, W.V.; Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A., Vapor Pressure, Heat Capacity, and Density along the Saturated Line, Measurements for Dimethyl Isophthalate, Dimethyl Carbonate, 1,3,5-Trimethyl benzene, Pentafluorophenol, 4-tert-Butylcatechol, .alp, J. Chem. Eng. Data, 1997, 42, 1008-20. [all data]

Verevkin, 1999
Verevkin, Sergey P., Thermochemical investigation on α-methyl-styrene and parent phenyl substituted alkenes, Thermochimica Acta, 1999, 326, 1-2, 17-25, https://doi.org/10.1016/S0040-6031(98)00585-1 . [all data]

Steele, Chirico, et al., 1997, 2
Steele, W.V.; Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A., Vapor Pressure, Heat Capacity, and Density along the Saturation Line, Measurements for Dimethyl Isophthalate, Dimethyl Carbonate, 1,3,5-Triethylbenzene, Pentafluorophenol, 4- tert -Butylcatechol, α-Methylstyrene, and N , N '-Bis(2-hydroxyethyl)ethylenediamine, J. Chem. Eng. Data, 1997, 42, 6, 1008-1020, https://doi.org/10.1021/je970102d . [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]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [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]

Koppel, Schwarz, et al., 1974
Koppel, C.; Schwarz, H.; Bohlmann, F., Elektronenstossinduzierte fragmentierung von acetylenverbindungen. VIII. Struktur der stabilen und instabilen ionen[C₉H₉]⁺ aus isomeren C₉H₁₀- kohlenwasserstoffen, Org. Mass Spectrom., 1974, 8, 25. [all data]

Benito, Seidl, et al., 1973
Benito, I.; Seidl, H.; Bock, H., Efectos electronicos y estericos de sustituyentes alquilicos y silicicos sobre el sistema electronico π del estireno, Rev. Fac. Cienc. Univ. Oviedo, 1973, 14, 95. [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]

Chizhov, Timoshenko, et al., 1986
Chizhov, Y.V.; Timoshenko, M.M.; Kleimenov, V.I.; Borisov, Y.A.; Zol'nikova, G.P.; Kravtsov, D.N.; Kritskaya, I.I., Investigation of the mechanism of fragment coordination of aromatic molecules with transition metals by photoelectron spectroscopy - tricarbonyliron complexes, J. Struct. Chem., 1986, 27, 401. [all data]

Kobayashi, Yokota, et al., 1973
Kobayashi, T.; Yokota, K.; Nagakura, S., Photoelectron spectra of styrenes, J. Electron Spectrosc. Relat. Phenom., 1973, 3, 449. [all data]

Bartmess and Burnham, 1984
Bartmess, J.E.; Burnham, R., Effect of central substituents on the gas phase acidities of propenes, J. Org. Chem., 1984, 49, 1382. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, 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
  Pc	Critical pressure
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  ΔcH°gas	Enthalpy of combustion of gas at standard conditions
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions
  ρc	Critical density

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