Benzaldehyde, 4-methyl-
- Formula: C8H8O
- Molecular weight: 120.1485
- IUPAC Standard InChI: InChI=1S/C8H8O/c1-7-2-4-8(6-9)5-3-7/h2-6H,1H3
- IUPAC Standard InChIKey: FXLOVSHXALFLKQ-UHFFFAOYSA-N
- CAS Registry Number: 104-87-0
- 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. - Species with the same structure:
- Other names: p-Tolualdehyde; p-Formyltoluene; p-Methylbenzaldehyde; p-Toluylaldehyde; p-Tolylaldehyde; 4-Methylbenzaldehyde; 4-Tolualdehyde; Paratolualdehyde; PTAL; NSC 2224
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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
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
View reactions leading to C8H8O+ (ion structure unspecified)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| Proton affinity (review) | 851.8 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
| Quantity | Value | Units | Method | Reference | Comment |
| Gas basicity | 820.0 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Electron affinity determinations
| EA (eV) | Method | Reference | Comment |
|---|---|---|---|
| 0.373 ± 0.017 | ECD | Wentworth, Kao, et al., 1975 | B |
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 9.33 ± 0.05 | EI | Foffani, Pignataro, et al., 1964 | RDSH |
| 9.34 | PE | Gal, Geribaldi, et al., 1985 | Vertical value; LBLHLM |
De-protonation reactions
C8H7O- + =
By formula: C8H7O- + H+ = C8H8O
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 1505. ± 10. | kJ/mol | G+TS | Kahn, Hehre, et al., 1984 | gas phase; value altered from reference due to change in acidity scale; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 1475. ± 9.6 | kJ/mol | IMRE | Kahn, Hehre, et al., 1984 | gas phase; value altered from reference due to change in acidity scale; 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]
Wentworth, Kao, et al., 1975
Wentworth, W.E.; Kao, L.W.; Becker, R.S.,
Electron affinities of substituted aromatic compounds,
J. Phys. Chem., 1975, 79, 1161. [all data]
Foffani, Pignataro, et al., 1964
Foffani, A.; Pignataro, S.; Cantone, B.; Grasso, F.,
Ionization potentials and substituent effects for aromatic carbonyl compounds,
Z. Physik. Chem. (Frankfurt), 1964, 42, 221. [all data]
Gal, Geribaldi, et al., 1985
Gal, J.-F.; Geribaldi, S.; Pfister-Guillouzo, G.; Morris, D.G.,
Basicity of the carbonyl group. Part 12. Correlations between ionization potentials and lewis basicities in aromatic carbonyl compounds,
J. Chem. Soc. Perkin Trans. 2, 1985, 103. [all data]
Kahn, Hehre, et al., 1984
Kahn, S.D.; Hehre, W.J.; Bartmess, J.E.; Caldwell, G.,
Effect of Metal Complexation on the Gas-phase Acidities of Alkylbenzenes,
Organomet., 1984, 3, 11, 1740, https://doi.org/10.1021/om00089a024
. [all data]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
EA Electron affinity 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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