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)
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Phase change data
  • Gas phase ion energetics data
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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Phase change data

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

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
AC - William E. Acree, Jr., James S. Chickos
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of sublimation

Enthalpy of fusion

Entropy of fusion

Gas phase ion energetics data

Go To: Top, Phase change data, Gas Chromatography, 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

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

Gas Chromatography

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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

Normal alkane RI, non-polar column, custom temperature program

View large format table.

References

Go To: Top, Phase change data, Gas phase ion energetics data, Gas Chromatography, Notes

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

Andrews, Lynn, et al., 1926
Andrews, D.H.; Lynn, G.; Johnston, J., The Heat Capacities and Heat of Crystallization of Some Isomeric Aromatic Compounds, J. Am. Chem. Soc., 1926, 48, 1274. [all data]

Nabavian, Sabbah, et al., 1977
Nabavian, P.M.; Sabbah, R.; Chastel, R.; Laffitte, M., Thermodynamique de composes azotes. II. Etude thermochimique des acides aminobenzoiques, de la pyrimidine, de l'uracile et de la thymine., J. Chim. Phys., 1977, 74, 115-126. [all data]

Sabbah, Chastelet, et al., 1974
Sabbah, R.; Chastelet, R.; Laffitte, M., Thermodynamic de composès azotes. I. Etude calorimètrique des enthalpies de sublimation des trios acides aminobenzoïques, Can. J. Chem., 1974, 52, 2201. [all data]

Sabbah, Chastel, et al., 1974
Sabbah, Raphaël; Chastel, Raymond; Laffitte, Marc, Thermodynamique de composés azotés. I. Etude calorimétrique des enthalpies de sublimation des trois acides aminobenzoïques, Can. J. Chem., 1974, 52, 12, 2201-2205, https://doi.org/10.1139/v74-319 . [all data]

Nabavian, Sabbah, et al., 1977, 2
Nabavian, M.; Sabbah, R.; Chastel, R.; Laffitte, M., J. Chim. Phys.Phys.-Chim. Biol., 1977, 74, 115. [all data]

de Kruif, Voogd, et al., 1979
de Kruif, C.G.; Voogd, J.; Offringa, J.C.A., Enthalpies of sublimation and vapour pressures of 14 amino acids and peptides, The Journal of Chemical Thermodynamics, 1979, 11, 7, 651-656, https://doi.org/10.1016/0021-9614(79)90030-2 . [all data]

Gracin and Rasmuson, 2004
Gracin, Sandra; Rasmuson, Åke C., Polymorphism and Crystallization of p -Aminobenzoic Acid, Crystal Growth & Design, 2004, 4, 5, 1013-1023, https://doi.org/10.1021/cg049954h . [all data]

Rotich, Glass, et al., 2001
Rotich, M.K.; Glass, B.D.; Brown, M.E., Journal of Thermal Analysis and Calorimetry, 2001, 64, 2, 681-688, https://doi.org/10.1023/A:1011584125859 . [all data]

Acree, 1991
Acree, William E., Thermodynamic properties of organic compounds: enthalpy of fusion and melting point temperature compilation, Thermochimica Acta, 1991, 189, 1, 37-56, https://doi.org/10.1016/0040-6031(91)87098-H . [all data]

Andrews, Lynn, et al., 1926, 2
Andrews, D.H.; Lynn, G.; Johnston, J., The heat capacities and heat of crystallization of some isomeric aromatic compounds, J. Am. Chem. Soc., 1926, 48, 1274-1287. [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]

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]

Ardrey and Moffat, 1981
Ardrey, R.E.; Moffat, A.C., Gas-liquid chromatographic retention indices of 1318 substances of toxicological interest on SE-30 or OV-1 stationary phase, J. Chromatogr., 1981, 220, 3, 195-252, https://doi.org/10.1016/S0021-9673(00)81925-1 . [all data]

Notes

Go To: Top, Phase change data, Gas phase ion energetics data, Gas Chromatography, References

• Symbols used in this document:
  

  AE	Appearance energy
  Tfus	Fusion (melting) point
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy 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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