3,5-Dimethylpyrazole

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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
Tboil491.2KN/AWeast and Grasselli, 1989BS
Quantity Value Units Method Reference Comment
Δsub83.4 ± 2.4kJ/molCRibeiro da Silva, Ferreira, et al., 2001AC

Enthalpy of sublimation

ΔsubH (kJ/mol) Temperature (K) Method Reference Comment
83.3 ± 0.2301.MEElguero, Yranzo, et al., 1991AC

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

C5H7N2- + Hydrogen cation = 3,5-Dimethylpyrazole

By formula: C5H7N2- + H+ = C5H8N2

Quantity Value Units Method Reference Comment
Δr1480. ± 8.8kJ/molG+TSTaft, 1987gas phase; value altered from reference due to change in acidity scale
Quantity Value Units Method Reference Comment
Δr1450. ± 8.4kJ/molIMRETaft, 1987gas phase; value altered from reference due to change in acidity scale

IR Spectrum

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Data compiled by: Coblentz Society, Inc.


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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Mass 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 Japan AIST/NIMC Database- Spectrum MS-NW-6290
NIST MS number 234855

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References

Go To: Top, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]

Ribeiro da Silva, Ferreira, et al., 2001
Ribeiro da Silva, Maria D.M.C.; Ferreira, Susana C.C.; Rodrigues, Ivone A.P.; da Silva, Luís C.M.; Acree Jr, William E.; Pandey, Siddharth; Roy, Lindsay E., Experimental standard molar enthalpies of formation of crystalline 3,5-dimethylpyrazole, 3,5-dimethyl-4-nitrosopyrazole, 1,3,5-trimethyl-4-nitrosopyrazole, and 3,5-dimethyl-1-phenyl-4-nitrosopyrazole, The Journal of Chemical Thermodynamics, 2001, 33, 10, 1227-1235, https://doi.org/10.1006/jcht.2000.0768 . [all data]

Elguero, Yranzo, et al., 1991
Elguero, Jose; Yranzo, Gloria I.; Laynez, Jose; Jimenez, Pilar; Menendez, Margarita; Catalan, Javier; De Paz, Jose Luis G.; Anvia, Frederick; Taft, Robert W., Effect of the replacement of a methyl by a trifluoromethyl group on the acid-base properties of pyrazoles, J. Org. Chem., 1991, 56, 12, 3942-3947, https://doi.org/10.1021/jo00012a030 . [all data]

Taft, 1987
Taft, R.W., The Nature and Analysis of Substitutent Electronic Effects, Personal communication. See also Prog. Phys. Org. Chem., 1987, 16, 1. [all data]


Notes

Go To: Top, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), References