4-Aminobenzoic acid

• Formula: C₇H₇NO₂
• Molecular weight: 137.1360
• IUPAC Standard InChI: InChI=1S/C7H7NO2/c8-6-3-1-5(2-4-6)7(9)10/h1-4H,8H2,(H,9,10) Copy

  
• IUPAC Standard InChIKey: ALYNCZNDIQEVRV-UHFFFAOYSA-N Copy
• CAS Registry Number: 150-13-0
• 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: p-Aminobenzoic acid; Aminobenzoic Acid; Benzoic acid, 4-amino-; Benzoic acid, p-amino-; p-Carboxyaniline; p-Carboxyphenylamine; Amben; anti-Chromotrichia Factor; Anticanitic vitamin; Chromotrichia factor; Hachemina; Pabacyd; Pabafilm; Pabamine; Paraminol; Paranate; PAB; PABA; Trichochromogenic Factor; Vitamin BX; Vitamin H'; 4-Carboxyaniline; γ-Aminobenzoic acid; Aminobenzoic acid, para; Bacterial vitamin H1; Pabanol; Super Shade by Coppertone; 1-Amino-4-carboxybenzene; Kyselina p-aminobenzoova; Sunbrella; RVPaba Lipstick; para-Aminobenzoic acid; Romavit; Aniline-4-carboxylic acid; Anticantic vitamin; Pabagel; component of Presun; 8014-65-1; component of Presun (Salt/Mix)
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• Information on this page:
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
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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 by: John E. Bartmess

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

C₇H₆NO₂^- +  =

By formula: C₇H₆NO₂^- + H⁺ = C₇H₇NO₂

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

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

View reactions leading to C₇H₇NO₂⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₇H₆NO₂^- +  =

By formula: C₇H₆NO₂^- + H⁺ = C₇H₇NO₂

References

Go To: Top, Reaction thermochemistry data, 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.

Kebarle and McMahon, 1977
Kebarle, P.; McMahon, T.B., Intrinsic Acidities of Substituted Phenols and Benzoic Acids Determined by Gas Phase Proton Transfer Equilibria, J. Am. Chem. Soc., 1977, 99, 7, 2222, https://doi.org/10.1021/ja00449a032 . [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]

Tobita, Tajima, et al., 1984
Tobita, S.; Tajima, S.; Tsuchiya, T., The substituent effect on the single and double hydrogen atom transfer reactions in para-substituted benzoic acid isobutyl esters, Org. Mass Spectrom., 1984, 19, 326. [all data]

Meeks, Wahlborg, et al., 1981
Meeks, J.; Wahlborg, A.; McGlynn, S.P., Photoelectron spectroscopy of carbonyls: Benzoic acid and its derivatives, J. Electron Spectrosc. Relat. Phenom., 1981, 22, 43. [all data]

Benoit, 1973
Benoit, F., Substituent effects in mass spectrometry. III. Substituent effects in the dissociation of the molecular ions of para and meta subtituted benzoic acids, Org. Mass Spectrom., 1973, 7, 295. [all data]

Notes

Go To: Top, Reaction thermochemistry data, 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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