Benzoic acid, 3-methyl-

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Gas phase thermochemistry data

Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.

Quantity Value Units Method Reference Comment
Δfgas-78.37 ± 0.33kcal/molCcbColomina, Jimenez, et al., 1986see Colomina, Boned, et al., 1961; ALS
Δfgas-78.66kcal/molN/ACorral, 1960Value computed using ΔfHsolid° value of -426.1±1.0 kj/mol from Corral, 1960 and ΔsubH° value of 97.0 kj/mol from Colomina, Jimenez, et al., 1986.; DRB

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Mass spectrum (electron ionization), 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
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

View reactions leading to C8H8O2+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
Proton affinity (review)198.3kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity190.9kcal/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
9.4 ± 0.2EIBenoit, 1973LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C7H7+12.5 ± 0.2COOHEIBenoit, 1973LLK
C8H7O+12.4 ± 0.2OHEIBenoit, 1973LLK

De-protonation reactions

C8H7O2- + Hydrogen cation = Benzoic acid, 3-methyl-

By formula: C8H7O2- + H+ = C8H8O2

Quantity Value Units Method Reference Comment
Δr340.6 ± 2.1kcal/molG+TSKebarle and McMahon, 1977gas phase; B
Δr340.4 ± 2.1kcal/molG+TSDecouzon, Exner, et al., 1996gas phase; Relative to benzoate at 333.0 kcal/mol; B
Quantity Value Units Method Reference Comment
Δr333.6 ± 2.0kcal/molIMREKebarle and McMahon, 1977gas phase; B
Δr333.4 ± 2.0kcal/molIMREDecouzon, Exner, et al., 1996gas phase; Relative to benzoate at 333.0 kcal/mol; B

Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, 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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Mass spectrum
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Additional Data

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Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin NIST Mass Spectrometry Data Center, 1998.
NIST MS number 291073

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Gas Chromatography

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

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, temperature ramp

View large format table.

Column type Active phase I Reference Comment
CapillaryUltra-11249.Okumura, 199125. m/0.32 mm/0.25 μm, He, 3. K/min; Tstart: 80. C; Tend: 260. C

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

View large format table.

Column type Active phase I Reference Comment
CapillaryHP-5MS1325.Alissandrakis, Kibaris, et al., 200530. m/0.25 mm/0.25 μm, He; Program: 40C(3min) => 2C/min => 180C => 10C/min => 250C(5min)

References

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), Gas Chromatography, 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., 1986
Colomina, M.; Jimenez, P.; Roux, M.V.; Turrion, C., Propiedades termoquimicas de derivados del acido benzoico. XIII. Presiones de vapor y entalpias de sublimacion y formacion de los acidos toluicos, An. Quim., 1986, 82, 126-130. [all data]

Colomina, Boned, et al., 1961
Colomina, M.; Boned, M.L.; Turrion, C., Investigaciones termoquimicas sobre los acidos alquilbenzoicos. I. Acidos toluicos, An. Fis. Quim., 1961, 57, 655-664. [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]

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]

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]

Decouzon, Exner, et al., 1996
Decouzon, M.; Exner, O.; Gal, J.-F.; Maria, P.-C., Non-classical Buttressing Effect: Gas-phase Ionization of Some Methyl Substituted Benzoic Acids, J. Chem. Soc. Perkin Trans., 1996, 2, 4, 475, https://doi.org/10.1039/p29960000475 . [all data]

Okumura, 1991
Okumura, T., retention indices of environmental chemicals on methyl silicone capillary column, Journal of Environmental Chemistry (Japan), 1991, 1, 2, 333-358, https://doi.org/10.5985/jec.1.333 . [all data]

Alissandrakis, Kibaris, et al., 2005
Alissandrakis, E.; Kibaris, A.C.; Tarantilis, P.A.; Harizanis, P.C.; Polissiou, M., Flavour compounds of Greek cotton honey, J. Sci. Food Agric., 2005, 85, 9, 1444-1452, https://doi.org/10.1002/jsfa.2124 . [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), Gas Chromatography, References