Butanoic acid, 3-methyl-
- Formula: C5H10O2
- Molecular weight: 102.1317
- IUPAC Standard InChI: InChI=1S/C5H10O2/c1-4(2)3-5(6)7/h4H,3H2,1-2H3,(H,6,7)
- IUPAC Standard InChIKey: GWYFCOCPABKNJV-UHFFFAOYSA-N
- CAS Registry Number: 503-74-2
- 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: Isovaleric acid; β-Methylbutyric acid; Acetic acid, isopropyl-; Delphinic acid; Isopentanoic acid; Isopropylacetic acid; 3-Methylbutanoic acid; 3-Methylbutyric acid; iso-C4H9COOH; Butyric acid, 3-methyl-; Isovalerianic acid; Kyselina isovalerova; 3-Methyl-n-butyric acid; NSC 62783; Isobutylformic acid; 3-methylbutanoic acid (isovaleric acid); Methylbutanoic acid
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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 compiled as indicated in comments:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 10.51 | PE | Watanabe, Yokoyama, et al., 1973 | Vertical value; LLK |
Appearance energy determinations
| Ion | AE (eV) | Other Products | Method | Reference | Comment |
|---|---|---|---|---|---|
| C2H4O2+ | 10.8 ± 0.1 | C3H6 | EI | Audier, Milliet, et al., 1985 | LBLHLM |
| C2H5O2+ | 10.4 ± 0.1 | C3H5 | EI | Audier, Milliet, et al., 1985 | LBLHLM |
De-protonation reactions
C5H9O2- + =
By formula: C5H9O2- + H+ = C5H10O2
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 1446. ± 8.8 | kJ/mol | G+TS | Caldwell, Renneboog, et al., 1989 | gas phase; B |
| ΔrH° | 1451. ± 8.8 | kJ/mol | G+TS | Taft and Topsom, 1987 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 1416. ± 8.4 | kJ/mol | IMRE | Caldwell, Renneboog, et al., 1989 | gas phase; B |
| ΔrG° | 1421. ± 8.4 | kJ/mol | IMRE | Taft and Topsom, 1987 | 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.
Watanabe, Yokoyama, et al., 1973
Watanabe, I.; Yokoyama, Y.; Ikeda, S.,
Lone pair ionization potentials of carboxylic acids determined by He(I) photoelectron spectroscopy,
Bull. Chem. Soc. Jpn., 1973, 46, 1959. [all data]
Audier, Milliet, et al., 1985
Audier, H.; Milliet, A.; Sozzi, G.,
Isomerisation des cation radicaux acides pentanoique et methyl-3-butanoique in phase gazeuse,
Bull. Soc. Chim. France, 1985, 5, 833. [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]
Taft and Topsom, 1987
Taft, R.W.; Topsom, R.D.,
The Nature and Analysis of Substituent Effects,
Prog. Phys. Org. Chem., 1987, 16, 1. [all data]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance 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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