Benzene, 1-bromo-4-methyl-

• Formula: C₇H₇Br
• Molecular weight: 171.034
• IUPAC Standard InChI: InChI=1S/C7H7Br/c1-6-2-4-7(8)5-3-6/h2-5H,1H3 Copy

  
• IUPAC Standard InChIKey: ZBTMRBYMKUEVEU-UHFFFAOYSA-N Copy
• CAS Registry Number: 106-38-7
• Chemical structure:
  This structure is also available as a 2d Mol file
• Other names: Toluene, p-bromo-; p-Bromotoluene; p-Methylbromobenzene; p-Methylphenyl bromide; p-Tolyl bromide; 1-Bromo-4-methylbenzene; 4-Bromo-1-methylbenzene; 4-Bromotoluene; 4-Methyl-1-bromobenzene; 4-Methylbromobenzene; 4-Methylphenyl bromide; 1-Methyl-4-bromobenzene; Parabromotoluene; 4-Tolyl bromide; NSC 6531
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase ion energetics data

Go To: Top, 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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - 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
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₇H₆Br^- +  =

By formula: C₇H₆Br^- + H⁺ = C₇H₇Br

Mass spectrum (electron ionization)

Go To: Top, Gas phase ion energetics data, 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

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Additional Data

References

Go To: Top, 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.

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]

Baidin, Misharev, et al., 1985
Baidin, V.N.; Misharev, A.D.; Takhistov, V.V., Effect of alkyl substituents on the ionization potentials of halogenobenzenes, Zh. Org. Khim., 1985, 21, 817. [all data]

Lias and Ausloos, 1978
Lias, S.G.; Ausloos, P.J., eIonization energies of organic compounds by equilibrium measurements, J. Am. Chem. Soc., 1978, 100, 6027. [all data]

Johnstone and Mellon, 1973
Johnstone, R.A.W.; Mellon, F.A., Effects of induction and resonance in the calculation of ionization potentials of substituted benzenes by perturbation molecular orbital theory, J. Chem. Soc. Faraday Trans. 2, 1973, 69, 36. [all data]

Tajima and Tsuchiya, 1972
Tajima, S.; Tsuchiya, T., The effects of the repeller voltage and the shield voltage on appearance potential measurements by electron impact, Shitsuryo Bunseki, 1972, 20, 117. [all data]

Baker, May, et al., 1968
Baker, A.D.; May, D.P.; Turner, D.W., Molecular photoelectron spectroscopy. Part VII. The vertical ionisation potentials of benzene and some of its monosubstituted and 1,4-disubstituted derivatives, J. Chem. Soc. B, 1968, 22. [all data]

Watanabe, 1957
Watanabe, K., Ionization potentials of some molecules, J. Chem. Phys., 1957, 26, 542. [all data]

Tajima and Tsuchiya, 1973
Tajima, S.; Tsuchiya, T., Energetics consideration of C₅H₅⁺ ions produced from various precursors by electron impact, Bull. Chem. Soc. Jpn., 1973, 46, 3291. [all data]

Howe and Williams, 1969
Howe, I.; Williams, D.H., Calculation and qualitative predictions of mass spectra. Mono- and paradisubstituted benzenes, J. Am. Chem. Soc., 1969, 91, 7137. [all data]

McLafferty and Winkler, 1974
McLafferty, F.W.; Winkler, J., Gaseous tropylium, benzyl, tolyl, and norbornadienyl cations, J. Am. Chem. Soc., 1974, 96, 5182. [all data]

Wenthold, Wierschke, et al., 1994
Wenthold, P.G.; Wierschke, S.G.; Nash, J.J.; Squires, R.R., Biradical thermochemistry from collision-induced dissociation threshold energy measurements .2. Experimental and theoretical studies of the Mechanism and Thermochemistry of Formation of alph, J. Am. Chem. Soc., 1994, 116, 16, 7378, https://doi.org/10.1021/ja00095a048 . [all data]

Notes

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

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization 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
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.