2-Aminopyridine

• Formula: C₅H₆N₂
• Molecular weight: 94.1145
• IUPAC Standard InChI: InChI=1S/C5H6N2/c6-5-3-1-2-4-7-5/h1-4H,(H2,6,7) Copy

  
• IUPAC Standard InChIKey: ICSNLGPSRYBMBD-UHFFFAOYSA-N Copy
• CAS Registry Number: 504-29-0
• 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: 2-Pyridinamine; Pyridine, 2-amino-; α-Aminopyridine; α-Pyridinamine; α-Pyridylamine; β-Pyridylamine; o-Aminopyridine; 2-Pyridylamine; Amino-2 pyridine; 1,2-Dihydro-2-iminopyridine; NSC 431
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• Information on this page:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Phase change data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
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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

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 as indicated in comments:
B - John E. Bartmess
RCD - Robert C. Dunbar

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

C₅H₅N₂^- +  =

By formula: C₅H₅N₂^- + H⁺ = C₅H₆N₂

 +  = ( • )

By formula: Li⁺ + C₅H₆N₂ = (Li⁺ • C₅H₆N₂)

 +  = ( • )

By formula: Na⁺ + C₅H₆N₂ = (Na⁺ • C₅H₆N₂)

 +  = ( • )

By formula: K⁺ + C₅H₆N₂ = (K⁺ • C₅H₆N₂)

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
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

Ionization energy determinations

De-protonation reactions

C₅H₅N₂^- +  =

By formula: C₅H₅N₂^- + H⁺ = C₅H₆N₂

References

Go To: Top, Condensed phase thermochemistry 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.

Bickerton, Pilcher, et al., 1984
Bickerton, J.; Pilcher, G.; Al-Takhin, G., Enthalpies of combustion of the three aminopyridines and the three cyanopyridines, J. Chem. Thermodyn., 1984, 16, 373-378. [all data]

Meot-ner and Kafafi, 1988
Meot-ner, M.; Kafafi, S.A., Carbon Acidities of Aromatic Compounds, J. Am. Chem. Soc., 1988, 110, 19, 6297, https://doi.org/10.1021/ja00227a003 . [all data]

Kiefer, Zhang, et al., 1997
Kiefer, J.H.; Zhang, Q.; Kern, R.D.; Yao, J.; Jursic, B., Pyrolysis of Aromatic Azines: Pyrazine, Pyrimidine, and Pyridine, J. Phys. Chem. A, 1997, 101, 38, 7061, https://doi.org/10.1021/jp970211z . [all data]

Taft and Bordwell, 1988
Taft, R.W.; Bordwell, F.G., Structural and Solvent Effects Evaluated from Acidities Measured in Dimethyl Sulfoxide and in the Gas Phase, Acc. Chem. Res., 1988, 21, 12, 463, https://doi.org/10.1021/ar00156a005 . [all data]

Rodgers, 2001
Rodgers, M.T., Substituent Effects in the Binding of Alkali Metal Ions to Pyridines, Studied by Threshold Collision-Induced Dissociation and ab Initio Theory: The Aminopyridines, J. Phys. Chem. A, 2001, 105, 35, 8145, https://doi.org/10.1021/jp011555z . [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]

Kim, Thantu, et al., 1992
Kim, B.; Thantu, N.; Weber, P.M., High resolution photoelectron spectroscopy: The vibrational spectrum of the 2-aminopyridine cation, J. Chem. Phys., 1992, 97, 5384. [all data]

Guimon, Khayar, et al., 1982
Guimon, C.; Khayar, S.; Pfister-Guillouzo, G.; Claramunt, R.M.; Elguero, J., A direct photoelectron spectroscopy study of the 1-azidopyridine pyrolysis, Spectrosc. Lett., 1982, 15, 435. [all data]

Daisey and Sonnessa, 1972
Daisey, J.M.; Sonnessa, A.J., A study of the thermodynamic and spectral properties of molecular complexes of iodine with several aminopyridines, J. Phys. Chem., 1972, 76, 1895. [all data]

Stefanovic and Grutzmacher, 1974
Stefanovic, D.; Grutzmacher, H.F., The ionisation potential of some substituted pyridines, Org. Mass Spectrom., 1974, 9, 1052. [all data]

Kobayashi and Nagakura, 1974
Kobayashi, T.; Nagakura, S., Photoelectron spectra of aminopyridines and cyanopyridines, J. Electron Spectrosc. Relat. Phenom., 1974, 4, 207. [all data]

Gronneberg and Undheim, 1973
Gronneberg, T.; Undheim, K., Mass spectrometry of onium compounds - XV. ionization potentials of amino pyridines, Tetrahedron Lett., 1973, 3193. [all data]

Notes

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• Symbols used in this document:
  

  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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