1H-1,2,4-Triazole
- Formula: C2H3N3
- Molecular weight: 69.0653
- IUPAC Standard InChIKey: NSPMIYGKQJPBQR-UHFFFAOYSA-N
- 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:
- Other names: s-Triazole; 1,2,4-Triazole; 1,2,4-1H-Triazole; CGA-71019; Pyrrodiazole
- Information on this page:
- Other data available:
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Reaction thermochemistry data
Go To: Top, Gas phase ion energetics data, Gas Chromatography, 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:
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 344.2 ± 2.1 | kcal/mol | G+TS | Taft, 1991 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 336.9 ± 2.0 | kcal/mol | IMRE | Taft, 1991 | gas phase; B |
By formula: Na+ + C2H3N3 = (Na+ • C2H3N3)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 29.6 ± 1.2 | kcal/mol | CIDT | Rodgers and Armentrout, 2000 | RCD |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
0.0 | 0. | CIDT | Rodgers and Armentrout, 2000 | RCD |
By formula: C4H5N3O + H2O = C2H3N3 + C2H4O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -7.29 ± 0.06 | kcal/mol | Cm | Wadso, 1960 | solid phase; Heat of hydrolysis; ALS |
By formula: C4H11N + C4H5N3O = C6H13NO + C2H3N3
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -20.50 ± 0.06 | kcal/mol | Cm | Wadso, 1962 | solid phase; ALS |
By formula: C2H3N3 = C2H3N3
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 2.8 | kcal/mol | Eqk | Mauret, Fayet, et al., 1973 | liquid phase; solvent: Benzene; ALS |
By formula: C4H5N3O + C6H7N = C8H9NO + C2H3N3
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -17.28 ± 0.08 | kcal/mol | Cm | Wadso, 1962 | solid phase; ALS |
By formula: Li+ + C2H3N3 = (Li+ • C2H3N3)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 45.7 ± 1.9 | kcal/mol | CIDT | Rodgers and Armentrout, 2000 | RCD |
By formula: K+ + C2H3N3 = (K+ • C2H3N3)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 20.8 ± 1.2 | kcal/mol | CIDT | Rodgers and Armentrout, 2000 | RCD |
Gas phase ion energetics data
Go To: Top, Reaction thermochemistry data, Gas Chromatography, 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:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Proton affinity (review) | 211.8 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 204.6 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.8 | PE | Palmer, Simpson, et al., 1981 | LLK |
10.1 | PE | Palmer, Simpson, et al., 1981 | Vertical value; LLK |
10.6 | PE | Guimon, Pfister-Guillouzo, et al., 1980 | Vertical value; LLK |
10.0 | PE | Cradock, Findlay, et al., 1973 | Vertical value; LLK |
De-protonation reactions
C2H2N3- + =
By formula: C2H2N3- + H+ = C2H3N3
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 344.2 ± 2.1 | kcal/mol | G+TS | Taft, 1991 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 336.9 ± 2.0 | kcal/mol | IMRE | Taft, 1991 | gas phase; B |
Gas Chromatography
Go To: Top, 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: NIST Mass Spectrometry Data Center, William E. Wallace, director
Kovats' RI, non-polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Capillary | OV-101 | 110. | 1116. | Zhuravleva, 2000 | 50. m/0.3 mm/0.4 μm, He |
Capillary | OV-101 | 110. | 1116. | Golovnya, Kuz'menko, et al., 1999 | 50. m/0.3 mm/0.4 μm, He |
References
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Gas Chromatography, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
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]
Zhuravleva, 2000
Zhuravleva, I.L.,
Evaluation of the polarity and boiling points of nitrogen-containing heterocyclic compounds by gas chromatography,
Russ. Chem. Bull. (Engl. Transl.), 2000, 49, 2, 325-328, https://doi.org/10.1007/BF02494682
. [all data]
Golovnya, Kuz'menko, et al., 1999
Golovnya, R.V.; Kuz'menko, T.E.; Zhuravleva, I.L.,
Gas chromatographic indicator of the ability of five- and six-membered heterocyclic nitrogen-containing compounds for self-association in pure liquids,
Russ. Chem. Bull. (Engl. Transl.), 1999, 48, 4, 726-729, https://doi.org/10.1007/BF02496256
. [all data]
Notes
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Gas Chromatography, References
- Symbols used in this document:
T Temperature 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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