Acetylacetone

Data at NIST subscription sites:

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.


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

Quantity Value Units Method Reference Comment
IE (evaluated)8.85 ± 0.02eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)873.5kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity836.8kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
8.85 ± 0.05PEHouk, Davis, et al., 1973LLK
8.82 ± 0.02PIShigorin, Filyugina, et al., 1967RDSH
8.87 ± 0.03PIWatanabe, Nakayama, et al., 1962RDSH
9.63 ± 0.01PEHush, Livett, et al., 1987Vertical value; LBLHLM
9.15PECauletti, Furlani, et al., 1980Vertical value; LLK
9.00PESchweig, Vermeer, et al., 1974Vertical value; LLK
9.18 ± 0.07PEEvans, Hamnett, et al., 1972Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C4H5O2+10.7 ± 0.1CH3EIReichert and Westmore, 1969RDSH
C4H5O2+10.24CH3PIShigorin, Filyugina, et al., 1967RDSH

De-protonation reactions

C5H7O2- + Hydrogen cation = Acetylacetone

By formula: C5H7O2- + H+ = C5H8O2

Quantity Value Units Method Reference Comment
Δr1438. ± 8.8kJ/molG+TSTaft and Bordwell, 1988gas phase; at 330K: neutral enol/keto ratio should be 8:1 ( Strohmeier and Höhne, 1952); B
Δr1438. ± 9.6kJ/molG+TSCumming and Kebarle, 1978gas phase; At 500K: neutral enol/keto ratio is 1.7:1, Folkendt, Weiss-Lopez, et al., 1989. ΔH=-4.7 kcal/mol, enol favored. Carbonyls anti in anion, via calc: Irikura, 1999; B
Quantity Value Units Method Reference Comment
Δr1409. ± 8.4kJ/molIMRETaft and Bordwell, 1988gas phase; at 330K: neutral enol/keto ratio should be 8:1 ( Strohmeier and Höhne, 1952); B
Δr1408. ± 8.4kJ/molIMRECumming and Kebarle, 1978gas phase; At 500K: neutral enol/keto ratio is 1.7:1, Folkendt, Weiss-Lopez, et al., 1989. ΔH=-4.7 kcal/mol, enol favored. Carbonyls anti in anion, via calc: Irikura, 1999; 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]

Houk, Davis, et al., 1973
Houk, K.N.; Davis, L.P.; Newkome, G.R.; Duke, R.E., Jr.; Nauman, R.V., Photoelectron spectroscopy of cyclic β-diketones their enolone tautomers, J. Am. Chem. Soc., 1973, 95, 8364. [all data]

Shigorin, Filyugina, et al., 1967
Shigorin, D.N.; Filyugina, A.D.; Potapov, V.K., Role of intramolecular hydrogen bonding in the ionisation and dissociation of compounds, Zh. Fiz. Khim., 1967, 41, 2336, In original 1255. [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]

Hush, Livett, et al., 1987
Hush, N.S.; Livett, M.K.; Peel, J.B.; Willett, G.D., Variable-temperature ultraviolet photoelectron spectroscopy of the keto-enol tautomers of pentane-2,4-dione, Aust. J. Chem., 1987, 40, 599. [all data]

Cauletti, Furlani, et al., 1980
Cauletti, C.; Furlani, C.; Storto, G., Coordinative bond d-shell ionisations in the UV photoelectron spectra of bis({beta}-diketonato) cobalt (II) copper (II) complexes, their thio analogues, J. Electron Spectrosc. Relat. Phenom., 1980, 18, 329. [all data]

Schweig, Vermeer, et al., 1974
Schweig, A.; Vermeer, H.; Weidner, U., A photoelectron spectroscopic study of keto-enol tautomerism in acetylacetones - a new application of photoelectron spectroscopy, Chem. Phys. Lett., 1974, 26, 229. [all data]

Evans, Hamnett, et al., 1972
Evans, S.; Hamnett, A.; Orchard, A.F.; Lloyd, D.R., Study of the metal-oxygen bond in simple tris-chelate complexes by He(I) photoelectron spectroscopy, Faraday Discuss. Chem. Soc., 1972, 54, 227. [all data]

Reichert and Westmore, 1969
Reichert, C.; Westmore, J.B., Mass spectral studies of metal chelates. IV.Mass spectra, appearance potentials, and coordinate bond energies of bis(acetylacetonate)metal(II) complexes of the first transition series, Inorg. Chem., 1969, 8, 1012. [all data]

Taft and Bordwell, 1988
Taft, R.W.; Bordwell, F.G., Structural and Solvent Effects Evaluated from Acidities Measured in Dimethyl Sulfoxide and in the Gas Phase, Acc. Chem. Res., 1988, 21, 12, 463, https://doi.org/10.1021/ar00156a005 . [all data]

Strohmeier and Höhne, 1952
Strohmeier, W.; Höhne, I., Keto-Enol-Umwandlung des Acetylacteons in Gaszustand, Z. Naturfor., 1952, 7B, 184. [all data]

Cumming and Kebarle, 1978
Cumming, J.B.; Kebarle, P., Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A), Can. J. Chem., 1978, 56, 1. [all data]

Folkendt, Weiss-Lopez, et al., 1989
Folkendt, M.M.; Weiss-Lopez, B.E.; Chauvel, J.P., Jr.; True, N.S., Gas-Phase 1H NMR Studies of Keto-Enol Tautomerization of Acetylacetone, Methyl Acetoacetate, and Ethyl Acetoacetate, J. Phys. Chem., 1989, 89, 15, 3347, https://doi.org/10.1021/j100261a038 . [all data]

Irikura, 1999
Irikura, K.K., Acetylacetonate (acac) anion in the gas phase: predicted structures, vibrational spectra, and photodetachment energies, Int. J. Mass Spectrom., 1999, 187, 577-587, https://doi.org/10.1016/S1387-3806(98)14192-1 . [all data]


Notes

Go To: Top, Gas phase ion energetics data, References