Thiophene, 2-methyl-
- Formula: C5H6S
- Molecular weight: 98.166
- IUPAC Standard InChIKey: XQQBUAPQHNYYRS-UHFFFAOYSA-N
- CAS Registry Number: 554-14-3
- 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: 2-Methylthiophene; 2-Methylthiacyclopentadiene; 2-methylthiacyclopentadiene (2-methylthiophene)
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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
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Proton affinity (review) | 205.3 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 197.5 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.61 | CTS | Aloisi and Pignataro, 1973 | LLK |
8.63 ± 0.05 | EI | Linda, Marino, et al., 1971 | LLK |
8.14 | PE | Baker, Betteridge, et al., 1970 | RDSH |
8.59 | PE | Colonna, Distefano, et al., 1979 | Vertical value; LLK |
De-protonation reactions
C5H5S- + =
By formula: C5H5S- + H+ = C5H6S
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 379.8 ± 3.1 | kcal/mol | G+TS | DePuy, Kass, et al., 1988 | gas phase; Acid: 2-methylthiophene. Between MeOH, EtOH.; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 373.0 ± 3.0 | kcal/mol | IMRB | DePuy, Kass, et al., 1988 | gas phase; Acid: 2-methylthiophene. Between MeOH, EtOH.; 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]
Aloisi and Pignataro, 1973
Aloisi, G.G.; Pignataro, S.,
Molecular complexes of substituted thiophens with σ and π acceptors,
J. Chem. Soc. Faraday Trans. 1, 1973, 69, 534. [all data]
Linda, Marino, et al., 1971
Linda, P.; Marino, G.; Pignataro, S.,
A comparison of sensitivities to substituent effects of five- membered heteroaromatic rings in gas phase ionization,
J. Chem. Soc. B, 1971, 1585. [all data]
Baker, Betteridge, et al., 1970
Baker, A.D.; Betteridge, D.; Kemp, N.R.; Kirby, R.E.,
Application of photoelectron spectrometry to pesticide analysis. Photoelectron spectra of fivemembered heterocycles and related molecules,
Anal. Chem., 1970, 42, 1064. [all data]
Colonna, Distefano, et al., 1979
Colonna, F.P.; Distefano, G.; Guerra, M.; Jones, D.; Modelli, A.,
Furyl- and thienyl-mercury derivatives studied by means of ultraviolet photoelectron spectroscopy. Evidence for the participation in bonding of the vacant 6p π orbitals of mercury in bis-2-furyl-bis-2-thienylmercury,
J. Chem. Soc. Dalton Trans., 1979, 2037. [all data]
DePuy, Kass, et al., 1988
DePuy, C.H.; Kass, S.R.; Bean, G.P.,
Formation and Reactions of Heteroaromatic Anions in the Gas Phase,
J. Org. Chem., 1988, 53, 19, 4427, https://doi.org/10.1021/jo00254a001
. [all data]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
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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