Pyrazine

• Formula: C₄H₄N₂
• Molecular weight: 80.0880
• IUPAC Standard InChI: InChI=1S/C4H4N2/c1-2-6-4-3-5-1/h1-4H Copy

  
• IUPAC Standard InChIKey: KYQCOXFCLRTKLS-UHFFFAOYSA-N Copy
• CAS Registry Number: 290-37-9
• 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-Diazine; Paradiazine; Piazine; 1,4-Diazabenzene; 1,4-Diazine
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• Information on this page:
  • Reaction thermochemistry data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
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  • Gas Phase Kinetics Database
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Reaction 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 as indicated in comments:
B - John E. Bartmess
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

C₄H₃N₂^- +  =

By formula: C₄H₃N₂^- + H⁺ = C₄H₄N₂

3 +  =

By formula: 3H₂ + C₄H₄N₂ = C₄H₁₀N₂

 +  = ( • )

By formula: Li⁺ + C₄H₄N₂ = (Li⁺ • C₄H₄N₂)

 +  = ( • )

By formula: Na⁺ + C₄H₄N₂ = (Na⁺ • C₄H₄N₂)

 +  = ( • )

By formula: K⁺ + C₄H₄N₂ = (K⁺ • C₄H₄N₂)

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.

Meot-ner and Kafafi, 1988
Meot-ner, M.; Kafafi, S.A., Carbon Acidities of Aromatic Compounds, J. Am. Chem. Soc., 1988, 110, 19, 6297, https://doi.org/10.1021/ja00227a003 . [all data]

Kiefer, Zhang, et al., 1997
Kiefer, J.H.; Zhang, Q.; Kern, R.D.; Yao, J.; Jursic, B., Pyrolysis of Aromatic Azines: Pyrazine, Pyrimidine, and Pyridine, J. Phys. Chem. A, 1997, 101, 38, 7061, https://doi.org/10.1021/jp970211z . [all data]

Wren, Vogelhuber, et al., 2012
Wren, S.W.; Vogelhuber, K.M.; Garver, J.M.; Kato, S.; Sheps, L.; Bierbaum, V.M.; Lineberger, W.C., C-H Bond Strengths and Acidities in Aromatic Systems: Effects of Nitrogen Incorporation in Mono-, Di-, and Triazines, J. Am. Chem. Soc., 2012, 134, 15, 6584-6595, https://doi.org/10.1021/ja209566q . [all data]

Hafelinger and Steinmann, 1977
Hafelinger, G.; Steinmann, L., Heat of hydrogenation of compounds containing isolated and conjugted C=N bouble bonds, Angew. Chem. Int. Ed. Engl., 1977, 16, 47-48. [all data]

Amunugama and Rodgers, 2000
Amunugama, R.; Rodgers, M.T., Absolute Alkali Metal Ion Binding Affinities of Several Azines Determined by Threshold Collision-Induced Dissociation and Ab Initio Theory, Int. J. Mass Spectrom., 2000, 195/196, 439, https://doi.org/10.1016/S1387-3806(99)00145-1 . [all data]

Notes

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• Symbols used in this document:
  

  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
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