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
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• 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:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • References
  • Notes
• Other data available:
  • Gas Chromatography
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Gas phase 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Condensed phase 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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

Mass spectrum (electron ionization)

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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

Spectrum

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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.

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]

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]

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
  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions
  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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