1H-Pyrazole, 3-methyl-

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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

Quantity Value Units Method Reference Comment
Tboil477.2KN/AAldrich Chemical Company Inc., 1990BS
Quantity Value Units Method Reference Comment
Δvap15.8 ± 0.48kcal/molCRibeiro da Silva, Figueiredo, et al., 2008AC

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- + Hydrogen cation = 1H-Pyrazole, 3-methyl-

By formula: C4H5N2- + H+ = C4H6N2

Quantity Value Units Method Reference Comment
Δr356.0 ± 2.1kcal/molG+TSTaft, 1991gas phase
Quantity Value Units Method Reference Comment
Δr348.3 ± 2.0kcal/molIMRETaft, 1991gas phase

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

Quantity Value Units Method Reference Comment
Proton affinity (review)216.5kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity208.9kcal/molN/AHunter and Lias, 1998HL

De-protonation reactions

C4H5N2- + Hydrogen cation = 1H-Pyrazole, 3-methyl-

By formula: C4H5N2- + H+ = C4H6N2

Quantity Value Units Method Reference Comment
Δr356.0 ± 2.1kcal/molG+TSTaft, 1991gas phase; B
Quantity Value Units Method Reference Comment
Δr348.3 ± 2.0kcal/molIMRETaft, 1991gas phase; B

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

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Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin NIST Mass Spectrometry Data Center
NIST MS number 340715

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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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Column type Active phase Temperature (C) I Reference Comment
CapillaryOV-101110.930.Golovnya, Kuz'menko, et al., 2000He; Phase thickness: 0.4 μm
CapillaryOV-101110.930.Zhuravleva, 200050. m/0.3 mm/0.4 μm, He

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

View large format table.

Column type Active phase I Reference Comment
PackedSE-30930.Peng, Ding, et al., 1988He, Supelcoport and Chromosorb, 40. C @ 4. min, 10. K/min, 250. C @ 60. min; Column length: 3.05 m

References

Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), Gas Chromatography, Notes

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]

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]

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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