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
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• Other names: Pyridine oxide; Pyridine N-oxide
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • References
  • Notes
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Gas phase 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Condensed phase 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, 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: 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

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

Ionization energy determinations

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• SATURATED SOLUTION (CCl4 FOR 3800-1330, CS2 FOR 1330-450 CM^-1); Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

• gas

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

UV/Visible spectrum

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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: Victor Talrose, Eugeny B. Stern, Antonina A. Goncharova, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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

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• 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
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