Acetylacetone

• Formula: C₅H₈O₂
• Molecular weight: 100.1158
• IUPAC Standard InChI: InChI=1S/C5H8O2/c1-4(6)3-5(2)7/h3H2,1-2H3 Copy

  
• IUPAC Standard InChIKey: YRKCREAYFQTBPV-UHFFFAOYSA-N Copy
• CAS Registry Number: 123-54-6
• 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: 2,4-Pentanedione; Acetoacetone; Diacetylmethane; Pentane-2,4-dione; 2-Propanone, acetyl-; 2,4-Dioxopentane; 2,4-Pentadione; CH3COCH2COCH3; Acetone, acetyl-; ACAC; Pentanedione; Pentanedione-2,4; Acetyl 2-propanone; UN 2310; 2,4-Pentandione; Pentan-2,4-dione; NSC 5575
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • References
  • Notes
• Other data available:
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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Gas phase thermochemistry 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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Condensed phase thermochemistry 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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Phase change 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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos

Reduced pressure boiling point

Enthalpy of vaporization

Reaction thermochemistry 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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

C₅H₇O₂^- +  =

By formula: C₅H₇O₂^- + H⁺ = C₅H₈O₂

=

By formula: C₅H₈O₂ = C₅H₈O₂

 +  = ( • )

By formula: Cl^- + C₅H₈O₂ = (Cl^- • C₅H₈O₂)

Free energy of reaction

 +  = ( • )

By formula: I^- + C₅H₈O₂ = (I^- • C₅H₈O₂)

=

By formula: C₅H₈O₂ = C₆H₁₀O₃

=

By formula: C₅H₈O₂ = C₅H₈O₂

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
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

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₅H₇O₂^- +  =

By formula: C₅H₇O₂^- + H⁺ = C₅H₈O₂

Ion clustering 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
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

 +  = ( • )

By formula: Cl^- + C₅H₈O₂ = (Cl^- • C₅H₈O₂)

Free energy of reaction

 +  = ( • )

By formula: I^- + C₅H₈O₂ = (I^- • C₅H₈O₂)

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• VAPOR (9 MICROLITER AT 150 C); PERKIN-ELMER 180; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 2-3 CM^-1 cm^-1 resolution

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

• gas

Mass spectrum (electron ionization)

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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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

UV/Visible spectrum

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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 by: Victor Talrose, Eugeny B. Stern, Antonina A. Goncharova, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Hacking and Pilcher, 1979
Hacking, J.M.; Pilcher, G., Enthalpy of combustion of pentane-2,4-dione, J. Chem. Thermodyn., 1979, 11, 1015-1017. [all data]

Conrath, Van de Sande, et al., 1974
Conrath, k.; Van de Sande, C.; Vandewalle, M., Studies in organic mass spectrometry. XVI. A combined approach to the structures of ions generated from the molecular ions of acyclic β-diketones through loss of small neutral molecules, Org. Mass Spectrom., 1974, 9, 585-593. [all data]

Melia and Merrifield, 1969
Melia, T.P.; Merrifield, R., Thermal properties of acetylacetone, J. Appl. Chem., 1969, 19, 79-82. [all data]

Vilcu and Perisanu, 1979
Vilcu, R.; Perisanu, S., The standard enthalpies of formation of some C, H, O containing compounds, Rev. Roum. Chim., 1979, 24, 237-243. [all data]

Guinchant, 1918
Guinchant, M.J., Etude sur la fonction acide dans les derives metheniques et methiniques, Ann. Chem., 1918, 10, 30-84. [all data]

Nicholson, 1957
Nicholson, G.R., The heat of combustion of acetylacetone, J. Chem. Soc., 1957, 2431-2432. [all data]

Timmermans, 1921
Timmermans, J., The Freezing Points of Organic Substances IV. New Exp. Determinations, Bull. Soc. Chim. Belg., 1921, 30, 62. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

Irving and Wads, 1970
Irving, R.J.; Wads, I., Enthalpy of vaporization of organic compounds at 25°C. V. Acetylacetone, Acta Chem. Scand., 1970, 24, 589-592. [all data]

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]

Melia and Merrifield, 2007
Melia, T.P.; Merrifield, R., Thermal properties of acetylacetone, J. Appl. Chem., 2007, 19, 3, 79-82, https://doi.org/10.1002/jctb.5010190305 . [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Nakanishi and Toyama, 1972
Nakanishi, Koichiro; Toyama, Osamu, Vapor Pressure of Acetylacetone below Normal Boiling Point, Bull. Chem. Soc. Jpn., 1972, 45, 10, 3210-3211, https://doi.org/10.1246/bcsj.45.3210 . [all data]

Raviprasad and Venkateswara Rao, 1985
Raviprasad, A.; Venkateswara Rao, K., Vapour pressure of 2,4-pentanedione, The Journal of Chemical Thermodynamics, 1985, 17, 2, 117-121, https://doi.org/10.1016/0021-9614(85)90063-1 . [all data]

Inoue, Arai, et al., 1981
Inoue, Mikio; Arai, Yasuhiko; Saito, Shozaburo; Suzuki, Nobuo, Vapor-liquid equilibriums of acetylacetone-organic solvent systems, J. Chem. Eng. Data, 1981, 26, 3, 287-293, https://doi.org/10.1021/je00025a020 . [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]

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, 229-233. [all data]

Thompson and Allred, 1971
Thompson, D.W.; Allred, A.L., Keto-enol equilibria in 2,4-Pentanedione and 3,3-dideuterio-2,4-pentanedione, J. Phys. Chem., 1971, 75, 433-435. [all data]

Calmon, 1969
Calmon, J.P., Thermodynamic functions of enolization of aliphatic β-diketones, C. R. Acad. Sci. Paris, 1969, 268, 1435-1438. [all data]

French, Ikuta, et al., 1982
French, M.A.; Ikuta, S.; Kebarle, P., Hydrogen bonding of O-H and C-H hydrogen donors to Cl^-. Results from mass spectrometric measurement of the ion-molecule equilibria RH + Cl^- = RHCl^-, Can. J. Chem., 1982, 60, 1907. [all data]

Caldwell, Masucci, et al., 1989
Caldwell, G.W.; Masucci, J.A.; Ikonomou, M.G., Negative Ion Chemical Ionization Mass Spectrometry - Binding of Molecules to Bromide and Iodide Anions, Org. Mass Spectrom., 1989, 24, 1, 8, https://doi.org/10.1002/oms.1210240103 . [all data]

Folkendt, Weiss-Lopez, et al., 1985
Folkendt, M.M.; Weiss-Lopez, B.E.; Chauvel, J.P., Jr.; True, N.S., Gas-phase ¹H NMR studies of keto-enol tautomerism of acetylacetone, methyl acetoacetate, and ethyl acetoacetate, J. Phys. Chem., 1985, 89, 3347-3352. [all data]

Mines and Thompson, 1975
Mines, G.W.; Thompson, H., Infrared and photoelectron spectra, and keto-enol tautomerism of acetylacetones and acetoacetic esters, Proc. Roy. Soc. London A, 1975, 342, 327-339. [all data]

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, 2
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]

Bernasconi and Kamararioti, 1986
Bernasconi, C.F.; Kamararioti, A., Nucleophilic addition to olefins. 19. Abnormally high intrinsic barrier in the reaction of piperidine and morpholine with benzylideneacetylacetone, J. Am. Chem. Soc., 1986, 108, 24, 7744-7751. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, References

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  T	Temperature
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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