Pyridine, 1-oxide

• Formula: C₅H₅NO
• Molecular weight: 95.0993
• IUPAC Standard InChI: InChI=1S/C5H5NO/c7-6-4-2-1-3-5-6/h1-5H Copy

  
• IUPAC Standard InChIKey: ILVXOBCQQYKLDS-UHFFFAOYSA-N Copy
• CAS Registry Number: 694-59-7
• 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: Pyridine oxide; Pyridine N-oxide
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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.

Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Phase change data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos

Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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

3 +  = 3 + KClO₃

By formula: 3C₅H₅NO + ClK = 3C₅H₅N + KClO₃

3 +  = 3 + KBrO₃

By formula: 3C₅H₅NO + BrK = 3C₅H₅N + KBrO₃

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, References, Notes

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:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

Ionization energy determinations

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Notes

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

Shaofeng and Pilcher, 1988
Shaofeng, L.; Pilcher, G., Enthalpy of formation of pyridine-N-oxide: the dissociation enthalpy of the (N-O) bond, J. Chem. Thermodyn., 1988, 20, 463-465. [all data]

da Silva, Chagas, et al., 1988
da Silva, M.L.C.P.; Chagas, A.P.; Airoldi, C., Heterocyclic N-oxide ligands: A thermochemical study of adducts with zinc, cadmium, and mercury chlorides, J. Chem. Soc. Dalton Trans., 1988, 2113-2116. [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]

Maier, Muller, et al., 1975
Maier, J.P.; Muller, J.-F.; Kubota, T., 182. Ionisation energies and the electronic structures of the N-oxides of diazabenzenes, Helv. Chim. Acta, 1975, 58, 1634. [all data]

Weiner and Lattman, 1974
Weiner, M.A.; Lattman, M., Photoelectron spectra of 4-substituted pyridine N-oxides, Tetrahedron Lett., 1974, 1709. [all data]

Maier and Muller, 1974
Maier, J.P.; Muller, J.-F., Ionisation energies of pyridine N-oxides determined by photoelectron spectroscopy, J. Chem. Soc. Faraday Trans. 2, 1974, 70, 1991. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔsubH°	Enthalpy of sublimation at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.