Propanal, 2-methyl-
- Formula: C4H8O
- Molecular weight: 72.1057
- IUPAC Standard InChI: InChI=1S/C4H8O/c1-4(2)3-5/h3-4H,1-2H3
- IUPAC Standard InChIKey: AMIMRNSIRUDHCM-UHFFFAOYSA-N
- CAS Registry Number: 78-84-2
- 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: Isobutyraldehyde; α-Methylpropionaldehyde; Isobutanal; Isopropylaldehyde; Isopropylformaldehyde; 2-Methylpropanal; 2-Methylpropionaldehyde; iso-C3H7CHO; Isobutylaldehyde; Isobutyric aldehyde; 2-Methyl-1-propanal; Isobutyraldehyd; Propionaldehyde, 2-methyl-; Valine aldehyde; Isobutaldehyde; Isobutyryl aldehyde; Methyl propanal; NCI-C60968; UN 2045; Isobutyral; NSC 6739; 2-methylpropanal (isobutanal)
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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
L - 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 C4H8O+ (ion structure unspecified)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| IE (evaluated) | 9.71 ± 0.02 | eV | N/A | N/A | L |
| Quantity | Value | Units | Method | Reference | Comment |
| Proton affinity (review) | 190.6 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
| Quantity | Value | Units | Method | Reference | Comment |
| Gas basicity | 183.0 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 9.72 | PI | Traeger and McAdoo, 1986 | LBLHLM |
| 9.705 ± 0.005 | PE | Hernandez, Masclet, et al., 1977 | LLK |
| 9.69 ± 0.01 | PE | Cocksey, Eland, et al., 1971 | LLK |
| 9.74 ± 0.03 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
| 9.82 | PE | Tam, Yee, et al., 1974 | Vertical value; LLK |
Appearance energy determinations
| Ion | AE (eV) | Other Products | Method | Reference | Comment |
|---|---|---|---|---|---|
| C2H3O+ | 10.29 | C2H5 | PI | Traeger and McAdoo, 1986 | LBLHLM |
De-protonation reactions
C4H7O- + =
By formula: C4H7O- + H+ = C4H8O
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 366.8 ± 3.0 | kcal/mol | D-EA | Alconcel, Deyerl, et al., 2001 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 359.5 ± 3.1 | kcal/mol | H-TS | Alconcel, Deyerl, et al., 2001 | gas phase; 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]
Traeger and McAdoo, 1986
Traeger, J.C.; McAdoo, D.J.,
Decomposition thresholds and associated translational energy releases for eight C4H8O+ isomers,
Int. J. Mass Spectrom. Ion Processes, 1986, 68, 35. [all data]
Hernandez, Masclet, et al., 1977
Hernandez, R.; Masclet, P.; Mouvier, G.,
Spectroscopie de photoelectrons d'aldehydes et de cetones aliphatiques,
J. Electron Spectrosc. Relat. Phenom., 1977, 10, 333. [all data]
Cocksey, Eland, et al., 1971
Cocksey, B.J.; Eland, J.H.D.; Danby, C.J.,
The effect of alkyl substitution on ionisation potential,
J. Chem. Soc., 1971, (B), 790. [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]
Tam, Yee, et al., 1974
Tam, W.-C.; Yee, D.; Brion, C.E.,
Photoelectron spectra of some aldehydes and ketones,
J. Electron Spectrosc. Relat. Phenom., 1974, 4, 77. [all data]
Alconcel, Deyerl, et al., 2001
Alconcel, L.S.; Deyerl, H.J.; Continetti, R.E.,
Effects of alkyl substitution on the energetics of enolate anions and radicals,
J. Am. Chem. Soc., 2001, 123, 50, 12675-12681, https://doi.org/10.1021/ja0120431
. [all data]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy IE (evaluated) Recommended ionization 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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