1,3-Cyclobutanedione, 2,2,4,4-tetramethyl-

• Formula: C₈H₁₂O₂
• Molecular weight: 140.1797
• IUPAC Standard InChI: InChI=1S/C8H12O2/c1-7(2)5(9)8(3,4)6(7)10/h1-4H3 Copy

  
• IUPAC Standard InChIKey: RGCDVHNITQEYPO-UHFFFAOYSA-N Copy
• CAS Registry Number: 933-52-8
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Other names: Tetramethyl-1,3-cyclobutanedione; Tetramethylcyclobuta-1,3-dione; 1,1,3,3-Tetramethylcyclobutanedione; 2,2,4,4-Tetramethyl-1,3-cyclobutanedione; 2,2,4,4-Tetramethylcyclobutanedione; 2,2,4,4-Tetramethyl cyclobutane-1,3-dione; tetramethylcyclobutane-1,3-dione
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • IR Spectrum
  • Mass spectrum (electron ionization)
• 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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Reduced pressure boiling point

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:
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

Ionization energy determinations

Appearance energy determinations

References

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

Sellers, 1971
Sellers, P., Enthalpy of formation of tetramethyl-1,3-cyclobutane-dione, Acta Chem. Scand., 1971, 25, 2291-2294. [all data]

Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc., Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]

Olivares, Flesch, et al., 1984
Olivares, J.A.; Flesch, G.D.; Svec, H.J., Mass spectrometry of five ketene dimers, Int. J. Mass Spectrom. Ion Processes, 1984, 56, 293. [all data]

Dougherty, Brint, et al., 1978
Dougherty, D.; Brint, P.; McGlynn, S.P., Photoelectron spectroscopy of carbonyls. Lone-pair interactions in α-, β-, γ δ-dicarbonyls, J. Am. Chem. Soc., 1978, 100, 5597. [all data]

Cowan, Gleiter, et al., 1971
Cowan, D.O.; Gleiter, R.; Hashmall, J.A.; Heilbronner, E.; Hornung, V., Interaction between the orbitals of lone pair electrons in dicarbonyl compounds, Angew. Chem. Int. Ed. Engl., 1971, 10, 401. [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  Tboil	Boiling point
  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions
  ΔsubH°	Enthalpy of sublimation at standard conditions

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