1H-Pyrazole

• Formula: C₃H₄N₂
• Molecular weight: 68.0773
• IUPAC Standard InChI: InChI=1S/C3H4N2/c1-2-4-5-3-1/h1-3H,(H,4,5) Copy

  
• IUPAC Standard InChIKey: WTKZEGDFNFYCGP-UHFFFAOYSA-N Copy
• CAS Registry Number: 288-13-1
• 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: Pyrazole; 1,2-Diazole
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• Information on this page:
  • Reaction thermochemistry data
  • References
  • Notes
• Other data available:
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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
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

C₃H₃N₂^- +  =

By formula: C₃H₃N₂^- + H⁺ = C₃H₄N₂

 +  = ( • )

By formula: Li⁺ + C₃H₄N₂ = (Li⁺ • C₃H₄N₂)

 +  = ( • )

By formula: Na⁺ + C₃H₄N₂ = (Na⁺ • C₃H₄N₂)

 +  = ( • )

By formula: K⁺ + C₃H₄N₂ = (K⁺ • C₃H₄N₂)

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.

Gianola, Ichino, et al., 2006
Gianola, A.J.; Ichino, T.; Kato, S.; Bierbaum, V.M.; Lineberger, W.C., Thermochemical studies of pyrazolide, J. Phys. Chem. A, 2006, 110, 27, 8457-8466, https://doi.org/10.1021/jp057499+ . [all data]

Taft, Anvia, et al., 1986
Taft, R.W.; Anvia, F.; Taagepera, M.; Catalan, J.; Elgueroy, J., Electrostatic proximity effects in the relative basicities of pyrazole, imidazole, pyridazine, and pyrimidine, J. Am. Chem. Soc., 1986, 108, 3237. [all data]

Huang and Rodgers, 2002
Huang, H.; Rodgers, M.T., Sigma versus Pi interactions in alkali metal ion binding to azoles: Threshold collision-induced dissociation and ab initio theory studies, J. Phys. Chem. A, 2002, 106, 16, 4277, https://doi.org/10.1021/jp013630b . [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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