Home Symbol which looks like a small house Up Solid circle with an upward pointer in it

3,5-Dimethylpyrazole

Data at NIST subscription sites:

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.


Phase change data

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

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
Deltasub19.9 ± 0.57kcal/molCRibeiro da Silva, Ferreira, et al., 2001AC

Enthalpy of sublimation

DeltasubH (kcal/mol) Temperature (K) Method Reference Comment
19.9 ± 0.05301.MEElguero, Yranzo, et al., 1991AC

Reaction thermochemistry data

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

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
Deltar353.8 ± 2.1kcal/molG+TSTaft, 1987gas phase; value altered from reference due to change in acidity scale
Quantity Value Units Method Reference Comment
Deltar346.5 ± 2.0kcal/molIMRETaft, 1987gas phase; value altered from reference due to change in acidity scale

IR Spectrum

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

Data compiled by: Coblentz Society, Inc.


Mass spectrum (electron ionization)

Go To: Top, Phase change data, Reaction thermochemistry data, IR Spectrum, References, Notes

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

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

Mass spectrum
For Zoom
1.) Enter the desired X axis range (e.g., 100, 200)
2.) Check here for automatic Y scaling
3.) Press here to zoom

Additional Data

View image of digitized spectrum (can be printed in landscape orientation).

View spectrum image in SVG format.

Download spectrum in JCAMP-DX format.

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

All mass spectra in this site (plus many more) are available from the NIST/EPA/NIH Mass Spectral Library. Please see the following for information about the library and its accompanying search program.


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