1H-Pyrazole, 3-methyl-

• Formula: C₄H₆N₂
• Molecular weight: 82.1038
• IUPAC Standard InChI: InChI=1S/C4H6N2/c1-4-2-3-5-6-4/h2-3H,1H3,(H,5,6) Copy

  
• IUPAC Standard InChIKey: XKVUYEYANWFIJX-UHFFFAOYSA-N Copy
• CAS Registry Number: 1453-58-3
• 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: Pyrazole, 3-methyl-; Pyrazole, 5-methyl-; 3(5)-Methylpyrazole; 5-Methylpyrazole; Pyrazole, 3(or 5)-methyl-; 3-Methyl-1H-pyrazole; 3-Methylpyrazole
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• Information on this page:
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data
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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

Data compiled as indicated in comments:
B - John E. Bartmess

De-protonation reactions

C₄H₅N₂^- +  =

By formula: C₄H₅N₂^- + H⁺ = C₄H₆N₂

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

Gas Chromatography

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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

Kovats' RI, non-polar column, isothermal

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Van Den Dool and Kratz RI, non-polar column, temperature ramp

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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.

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]

Taft, 1991
Taft, R.W., , personal communication, Aug, 1991. [all data]

Golovnya, Kuz'menko, et al., 2000
Golovnya, R.V.; Kuz'menko, T.E.; Krikunova, N.I., The influence of alkyl substituents on the chromatographic indicator of self-association of N-containing heterocyclic compounds, Russ. Chem. Bull. (Engl. Transl.), 2000, 49, 2, 321-324, https://doi.org/10.1007/BF02494681 . [all data]

Zhuravleva, 2000
Zhuravleva, I.L., Evaluation of the polarity and boiling points of nitrogen-containing heterocyclic compounds by gas chromatography, Russ. Chem. Bull. (Engl. Transl.), 2000, 49, 2, 325-328, https://doi.org/10.1007/BF02494682 . [all data]

Peng, Ding, et al., 1988
Peng, C.T.; Ding, S.F.; Hua, R.L.; Yang, Z.C., Prediction of Retention Indexes I. Structure-Retention Index Relationship on Apolar Columns, J. Chromatogr., 1988, 436, 137-172, https://doi.org/10.1016/S0021-9673(00)94575-8 . [all data]

Notes

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

• Symbols used in this document:
  

  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

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