Isocrotonic acid
- Formula: C4H6O2
- Molecular weight: 86.0892
- IUPAC Standard InChI: InChI=1S/C4H6O2/c1-2-3-4(5)6/h2-3H,1H3,(H,5,6)/b3-2-
- IUPAC Standard InChIKey: LDHQCZJRKDOVOX-IHWYPQMZSA-N
- CAS Registry Number: 503-64-0
- 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:
- Stereoisomers:
- Other names: 2-Butenoic acid, (Z)-; Crotonic acid, (Z)-; (Z)-Crotonic acid; (Z)-2-Butenoic acid; cis-Crotonic Acid; cis-2-Butenoic Acid; (Z)-CH3CH=CHCOOH; (2Z)-2-Butenoic acid
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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 compiled as indicated in comments:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 10.08 | PE | Holmes, Terlouw, et al., 1979 | LLK |
De-protonation reactions
C4H5O2- + =
By formula: C4H5O2- + H+ = C4H6O2
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 346.1 ± 2.2 | kcal/mol | G+TS | Caldwell, Renneboog, et al., 1989 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 337.3 ± 2.8 | kcal/mol | CIDC | Graul, Schnute, et al., 1990 | gas phase; B |
| ΔrG° | 339.1 ± 2.0 | kcal/mol | IMRE | Caldwell, Renneboog, et al., 1989 | 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.
Holmes, Terlouw, et al., 1979
Holmes, J.L.; Terlouw, J.K.; Vijfhuizen, P.C.; A'Campo, C.,
Metastable ion studies XII-Molecular and fragment ion structures for isomeric C4H6O2 acids,
Org. Mass Spectrom., 1979, 14, 204. [all data]
Caldwell, Renneboog, et al., 1989
Caldwell, G.; Renneboog, R.; Kebarle, P.,
Gas Phase Acidities of Aliphatic Carboxylic Acids, Based on Measurements of Proton Transfer Equilibria,
Can. J. Chem., 1989, 67, 4, 661, https://doi.org/10.1139/v89-092
. [all data]
Graul, Schnute, et al., 1990
Graul, S.T.; Schnute, M.E.; Squires, R.R.,
Gas-Phase Acidities of Carboxylic Acids and Alcohols from Collision-Induced Dissociation of Dimer Cluster Ions,
Int. J. Mass Spectrom. Ion Proc., 1990, 96, 2, 181, https://doi.org/10.1016/0168-1176(90)87028-F
. [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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