α-Methylstyrene
- Formula: C9H10
- Molecular weight: 118.1757
- IUPAC Standard InChIKey: XYLMUPLGERFSHI-UHFFFAOYSA-N
- 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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Gas phase ion energetics data
Go To: Top, 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)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Proton affinity (review) | 206.5 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 199.6 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.3 ± 0.1 | EI | Koppel, Schwarz, et al., 1974 | LLK |
8.18 ± 0.04 | EI | Benito, Seidl, et al., 1973 | LLK |
8.35 ± 0.01 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
8.50 | PE | Chizhov, Timoshenko, et al., 1986 | Vertical value; LBLHLM |
8.52 | PE | Kobayashi, Yokota, et al., 1973 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C9H9+ | 11.8 ± 0.1 | H | EI | Koppel, Schwarz, et al., 1974 | LLK |
De-protonation reactions
C9H9- + =
By formula: C9H9- + H+ = C9H10
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 385.6 ± 5.6 | kcal/mol | G+TS | Bartmess and Burnham, 1984 | gas phase; between H2O, MeOH; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 379.0 ± 5.5 | kcal/mol | IMRB | Bartmess and Burnham, 1984 | gas phase; between H2O, MeOH; B |
References
Go To: Top, 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.
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 ion energetics data, References
- Symbols used in this document:
AE Appearance energy ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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