2-Butenal
- Formula: C4H6O
- Molecular weight: 70.0898
- IUPAC Standard InChIKey: MLUCVPSAIODCQM-UHFFFAOYSA-N
- CAS Registry Number: 4170-30-3
- 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. - Stereoisomers:
- Other names: Crotonaldehyde; Crotonal; Crotonic aldehyde; Crotylaldehyde; β-Methylacrolein; Propylene aldehyde; Krotonaldehyd; Rcra waste number U053; UN 1143; But-2-enal; 1-Formylpropene; 2-Butenaldehyde; NSC 56354
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Gas phase ion energetics 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 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
View reactions leading to C4H6O+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Proton affinity (review) | 830.8 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 799.0 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.75 | PE | Masclet and Mouvier, 1978 | LLK |
9.73 ± 0.01 | PI | Watanabe, 1957 | RDSH |
9.86 ± 0.03 | PE | Klessinger and Gunkel, 1978 | Vertical value; LLK |
De-protonation reactions
C4H5O- + =
By formula: C4H5O- + H+ = C4H6O
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1484. ± 8.8 | kJ/mol | G+TS | Bartmess and Kiplinger, 1986 | gas phase; Acid: CH3CH=CHCHO; value altered from reference due to change in acidity scale; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1456. ± 8.4 | kJ/mol | IMRE | Bartmess and Kiplinger, 1986 | gas phase; Acid: CH3CH=CHCHO; 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]
Masclet and Mouvier, 1978
Masclet, P.; Mouvier, G.,
Etude par spectrometrie photoelectronique d'aldehydes et de cetones ethyleniques conjugues,
J. Electron Spectrosc. Relat. Phenom., 1978, 14, 77. [all data]
Watanabe, 1957
Watanabe, K.,
Ionization potentials of some molecules,
J. Chem. Phys., 1957, 26, 542. [all data]
Klessinger and Gunkel, 1978
Klessinger, M.; Gunkel, E.,
The electronic structure of polyenes and unsaturated carbonyl compounds,
Tetrahedron, 1978, 34, 3591. [all data]
Bartmess and Kiplinger, 1986
Bartmess, J.E.; Kiplinger, J.P.,
'Kinetic' vs. thermodynamic acidities of enones in the gas phase,
J. Org. Chem., 1986, 51, 2173. [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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