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:
  • Phase change data
  • Reaction thermochemistry data
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
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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
AC - William E. Acree, Jr., James S. Chickos

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 by: John E. Bartmess

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

C₄H₅N₂^- +  =

By formula: C₄H₅N₂^- + H⁺ = C₄H₆N₂

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.

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

Ribeiro da Silva, Figueiredo, et al., 2008
Ribeiro da Silva, Manuel A.V.; Figueiredo, Diogo F.; Cabral, Joana I.T.A., Thermochemical studies of 3-methylpyrazole and 1,3,5-trimethylpyrazole, The Journal of Chemical Thermodynamics, 2008, 40, 3, 369-374, https://doi.org/10.1016/j.jct.2007.09.001 . [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

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• Symbols used in this document:
  

  Tboil	Boiling point
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH°	Enthalpy of vaporization at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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