Quinoxaline

• Formula: C₈H₆N₂
• Molecular weight: 130.1466
• IUPAC Standard InChI: InChI=1S/C8H6N2/c1-2-4-8-7(3-1)9-5-6-10-8/h1-6H Copy

  
• IUPAC Standard InChIKey: XSCHRSMBECNVNS-UHFFFAOYSA-N Copy
• CAS Registry Number: 91-19-0
• 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: Benzoparadiazine; Benzopyrazine; Benzo[a]pyrazine; Phenopiazine; Phenpiazine; Quinazine; 1,4-Benzodiazine; 1,4-Diazanaphthalene; 1,4-Naphthyridine; USAF EK-7094
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• Information on this page:
  • Phase change data
  • Gas phase ion energetics data
  • IR Spectrum
  • UV/Visible spectrum
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Mass spectrum (electron ionization)
  • Gas Chromatography
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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:
BS - Robert L. Brown and Stephen E. Stein
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
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of sublimation

Enthalpy of fusion

Temperature of phase transition

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
L - Sharon G. Lias

Data compiled as indicated in comments:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
B - John E. Bartmess

Electron affinity determinations

Ionization energy determinations

IR Spectrum

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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

Gas Phase Spectrum

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Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.

Additional Data

UV/Visible spectrum

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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: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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Additional Data

References

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

Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc., Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]

Sabbah and Pemenzi, 1993
Sabbah, R.; Pemenzi, O., Energetics of intermolecular bonds in the three diazines: phthalazine, quinazoline and quinoxaline, C. R. Acad. Sci. Paris, Ser. II, 1993, 317, 5, 575. [all data]

Ribeiro da Silva and Matos, 1995
Ribeiro da Silva, M.A.V.; Matos, M.A.R., Thermochemical and theoretical studies of some benzodiazines, J. Chem. Soc. Faraday Trans., 1995, 91, 1907-1910. [all data]

da Silva, Matos, et al., 1995
da Silva, Manuel A.V. Ribeiro; Matos, M. Agostinha R.; Morais, Victor M.F., Thermochemical and theoretical studies of some benzodiazines, Faraday Trans., 1995, 91, 13, 1907, https://doi.org/10.1039/ft9959101907 . [all data]

Sabbah and Pemenzi, 1993, 2
Sabbah, R.; Pemenzi, O., Energetique des liaisons intermoleculaires dans les molecules de phthalazine, quinazoline, and quinoxaline, Compt. Rend. Acad. Sci. Paris, Series II, 1993, 317, 575-581. [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]

Dillow and Kebarle, 1989
Dillow, G.W.; Kebarle, P., Electron Affinities of aza-substituted polycyclic aromatic hydrocarbons, Can. J. Chem., 1989, 67, 10, 1628, https://doi.org/10.1139/v89-249 . [all data]

Brogli, Heilbronner, et al., 1972
Brogli, F.; Heilbronner, E.; Kobayashi, T., Photoelectron spectra of azabenzenes and azanaphthalenes: II. A reinvestigation of azanaphthalenes by high-resolution photoelectron spectroscopy, Helv. Chim. Acta, 1972, 55, 274. [all data]

Dewar and Worley, 1969
Dewar, M.J.S.; Worley, S.D., Photoelectron spectra of molecules. II.The ionization potentials of azabenzenes and azanaphthalenes, J. Chem. Phys., 1969, 51, 263. [all data]

Yencha and El-Sayed, 1968
Yencha, A.J.; El-Sayed, M.A., Lowest ionization potentials of some nitrogen heterocyclics, J. Chem. Phys., 1968, 48, 3469. [all data]

Van Den Ham and Van Der Meer, 1972
Van Den Ham, D.M.W.; Van Der Meer, D., The photoelectron spectra of the diazanaphthalenes, Chem. Phys. Lett., 1972, 12, 447. [all data]

Hirt and Cavagnol, 1956
Hirt, R.C.; Cavagnol, J.C., J. Chem. Phis., 1956, 25, 574. [all data]

Notes

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• Symbols used in this document:
  

  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttrs	Temperature of phase transition
  ΔfusH	Enthalpy of fusion
  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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