1H-1,2,4-Triazole

• Formula: C₂H₃N₃
• Molecular weight: 69.0653
• IUPAC Standard InChI: InChI=1S/C2H3N3/c1-3-2-5-4-1/h1-2H,(H,3,4,5) Copy

  
• IUPAC Standard InChIKey: NSPMIYGKQJPBQR-UHFFFAOYSA-N Copy
• CAS Registry Number: 288-88-0
• 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.
• Species with the same structure:
  • 4H-1,2,4-triazole
• Other names: s-Triazole; 1,2,4-Triazole; 1,2,4-1H-Triazole; CGA-71019; Pyrrodiazole
• Information on this page:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Ion clustering data
  • Gas Chromatography
• Options:
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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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.

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
ALS - 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

C₂H₂N₃^- +  =

By formula: C₂H₂N₃^- + H⁺ = C₂H₃N₃

 +  = ( • )

By formula: Na⁺ + C₂H₃N₃ = (Na⁺ • C₂H₃N₃)

Free energy of reaction

 +  =  + 

By formula: C₄H₅N₃O + H₂O = C₂H₃N₃ + C₂H₄O₂

 +  =  + 

By formula: C₄H₁₁N + C₄H₅N₃O = C₆H₁₃NO + C₂H₃N₃

=

By formula: C₂H₃N₃ = C₂H₃N₃

 +  =  + 

By formula: C₄H₅N₃O + C₆H₇N = C₈H₉NO + C₂H₃N₃

 +  = ( • )

By formula: Li⁺ + C₂H₃N₃ = (Li⁺ • C₂H₃N₃)

 +  = ( • )

By formula: K⁺ + C₂H₃N₃ = (K⁺ • C₂H₃N₃)

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

Ionization energy determinations

De-protonation reactions

C₂H₂N₃^- +  =

By formula: C₂H₂N₃^- + H⁺ = C₂H₃N₃

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

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, 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.

Jimenez, Roux, et al., 1989
Jimenez, P.; Roux, M.V.; Turrion, C., Thermochemical properties of N-heterocyclic compounds II. Enthalpies of combustion, vapour pressures, enthalpies of sublimation, and enthalpies of formation of 1,2,4-triazole and benzotriazole, J. Chem. Thermodyn., 1989, 21, 759-764. [all data]

Faour and Akasheh, 1985
Faour, M.; Akasheh, T.S., Heat of combustion of some N-heterocycle compounds. Part 1, J. Chem. Soc. Perkin Trans. 2, 1985, 811-713. [all data]

Masalitinova, Oleinikova, et al., 1984
Masalitinova, T.N.; Oleinikova, T.P.; Polyakova, L.P., Thermochemical study of 1,2,4-triazole as a reference substnace for the calorimetry of combustion of organonitrogen compounds, Ref. Zh., Khim.; Abstr. No. 7B3028, 1984, 0. [all data]

Aleksandrov, Osipova, et al., 1982
Aleksandrov, Yu.I.; Osipova, T.R.; Yuhkevich, V.F., Study of 1,2,4-triazole as a standard sample in the calorimetry of thoroughly nitrided organic compounds, Termodin. Organ. Soedin., 1982, 42-45. [all data]

Taft, 1991
Taft, R.W., , personal communication, Aug, 1991. [all data]

Rodgers and Armentrout, 2000
Rodgers, M.T.; Armentrout, P.B., Noncovalent Metal-Ligand Bond Energies as Studied by Threshold Collision-Induced Dissociation, Mass Spectrom. Rev., 2000, 19, 4, 215, https://doi.org/10.1002/1098-2787(200007)19:4<215::AID-MAS2>3.0.CO;2-X . [all data]

Wadso, 1960
Wadso, I., Heats of hydrolysis of N-acetylated imidazole, 1,2,4-triazole and tetrazole, Acta Chem. Scand., 1960, 14, 903-908. [all data]

Wadso, 1962
Wadso, I., Heats of aminolysis and hydrolysis of some N-acetyl compounds and of acetic anhydride, Acta Chem. Scand., 1962, 16, 471-478. [all data]

Mauret, Fayet, et al., 1973
Mauret, P.; Fayet, J.P.; Fabre, M.; Elguero, J.; Pardo, M.d.C., Tautomerism study of υ-triazole from dipolar moment measurements, J. Chim. Phys. Phys.-Chim. Biol., 1973, 70, 1483-1485. [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]

Palmer, Simpson, et al., 1981
Palmer, M.H.; Simpson, I.; Wheeler, J.R., Gas phase tautomerism in the triazoles and tetrazoles: A study by photoelectron spectroscopy and ab initio molecular orbital calculations, Z. Naturforsch. A:, 1981, 36, 1246. [all data]

Guimon, Pfister-Guillouzo, et al., 1980
Guimon, C.; Pfister-Guillouzo, G.; Bernardini, A.; Viallefont, P., A photoelectron study (HeI, HeII) of the tautomeric equilibrium of chloro- and bromo-1,2,4-triazoles, Tetrahedron, 1980, 36, 1071. [all data]

Cradock, Findlay, et al., 1973
Cradock, S.; Findlay, R.H.; Palmer, M.H., The molecular energy levels of the azoles: A study by photoelectron spectroscopy and ab initio molecular orbital calculations, Tetrahedron, 1973, 29, 2173. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  T	Temperature
  ΔfH°gas	Enthalpy of formation of gas 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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