Benzoic acid, 2,3-dimethyl-

• Formula: C₉H₁₀O₂
• Molecular weight: 150.1745
• IUPAC Standard InChI: InChI=1S/C9H10O2/c1-6-4-3-5-8(7(6)2)9(10)11/h3-5H,1-2H3,(H,10,11) Copy

  
• IUPAC Standard InChIKey: RIZUCYSQUWMQLX-UHFFFAOYSA-N Copy
• CAS Registry Number: 603-79-2
• 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: Hemellitic acid; 2,3-Dimethylbenzoic acid
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
  • IR Spectrum
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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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.

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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of solid

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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of sublimation

Enthalpy of fusion

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 by: John E. Bartmess

De-protonation reactions

C₉H₉O₂^- +  =

By formula: C₉H₉O₂^- + H⁺ = C₉H₁₀O₂

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

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), Notes

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

Colomina, Jimenez, et al., 1984
Colomina, M.; Jimenez, P.; Roux, M.V.; Turrion, C., Thermochemical properties of benzoic acid derivatives. XI. Vapour pressures and enthalpies of sublimation and formation of the six dimethylbenzoic acids, J. Chem. Thermodyn., 1984, 16, 1121-1127. [all data]

Colomina, Perez-Ossorio, et al., 1961
Colomina, M.; Perez-Ossorio, R.; Boned, M.L.; Panea, M.; Turrion, C., Investigaciones termoquimicas sobre los acidos alquilbenzoicos. II. Acidos dimetrilbenzoicos, Anal. Fisc. Quim. B, 1961, 57, 665-672. [all data]

Colomina, Perez Ossorio, et al., 1959
Colomina, M.; Perez Ossorio, R.; Boned, M.L.; Panea, M.; Turrion, C., Thermochemical investigations on methylsubstituted benzoic acids, Rpt. for the U.S. Dept. of the Army, European Research Office contract no. DA-91-508-EUC-358 by Instituto de Quimica Fisica Madrid, Spain, 1959, 1-36. [all data]

Corral, 1960
Corral, L.B., Investigaciones termoquimicas sobre los acidos toluicos y dimetilbenzoicos, Rev. R. Acad. Cienc., 1960, 54, 365-403. [all data]

Birch, Dean, et al., 1949
Birch, S.F.; Dean, R.A.; Fidler, F.A.; Lowry, R.A., The preparation of the c(10) monocyclic aromatic hydrocarbons, J. Am. Chem. Soc., 1949, 71, 1362. [all data]

Belhachemi, Ufnalsky, et al., 1996
Belhachemi, B.; Ufnalsky, W.; Derriche, Z., Determination of melting enthalpies and solubility curves in n-hexane of 2,3- and 3,5-dimethyl benzoic acids. Comparison with UNIFAC calculations, J. Chim. Phys. Phys.-Chim. Biol., 1996, 93, 6, 1117. [all data]

Decouzon, Ertl, et al., 1993
Decouzon, M.; Ertl, P.; Exner, O.; Gal, J.F.; Maria, P.C., Concepts of Sterically Hindered Resonance and Buttressing Effect - Gas-Phase Acidities of Methyl-Substituted Benzoic Acids and Basicities of, J. Am. Chem. Soc., 1993, 115, 25, 12071, https://doi.org/10.1021/ja00078a052 . [all data]

Notes

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• Symbols used in this document:
  

  Cp,solid	Constant pressure heat capacity of solid
  Tfus	Fusion (melting) 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
  ΔfusH	Enthalpy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔsubH°	Enthalpy of sublimation at standard conditions

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