1H-Imidazole
- Formula: C3H4N2
- Molecular weight: 68.0773
- IUPAC Standard InChI: InChI=1S/C3H4N2/c1-2-5-3-4-1/h1-3H,(H,4,5)
- IUPAC Standard InChIKey: RAXXELZNTBOGNW-UHFFFAOYSA-N
- CAS Registry Number: 288-32-4
- 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: Imidazole; Glyoxalin; Glyoxaline; Imidazol; Imutex; Methanimidamide, N,N'-1,2-ethenediyl-; Miazole; 1,3-Diaza-2,4-cyclopentadiene; 1,3-Diazole; Formamidine, N,N'-vinylene-; Iminazole; IMD; Pyrro(b)monazole; USAF EK-4733; NSC 60522
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Gas phase thermochemistry data
Go To: Top, 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:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°gas | 30.95 | kcal/mol | N/A | Zaheeruddin and Lodhi, 1991 | Value computed using ΔfHsolid° value of 60.0 kj/mol from Zaheeruddin and Lodhi, 1991 and ΔsubH° value of 69.5 kj/mol from Jimenez, Roux, et al., 1987.; DRB |
| ΔfH°gas | 33.29 ± 0.45 | kcal/mol | Cm | Guthrie and Pike, 1987 | Heat of hydrolysis; ALS |
| ΔfH°gas | 31.8 ± 0.1 | kcal/mol | Ccb | Jimenez, Roux, et al., 1987 | see Jimenez, Roux, et al., 1986; ALS |
| ΔfH°gas | 30.6 ± 1.8 | kcal/mol | Ccb | Bedford, Edmondson, et al., 1962 | ALS |
References
Go To: Top, Gas phase thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Zaheeruddin and Lodhi, 1991
Zaheeruddin, M.; Lodhi, Z.H.,
Enthalpies of formation of some cyclic compounds,
Phys. Chem. (Peshawar Pak.), 1991, 10, 111-118. [all data]
Jimenez, Roux, et al., 1987
Jimenez, P.; Roux, M.V.; Turrion, C.,
Thermochemical properties of N-heterocyclic compounds. I. Enthalpies of combustion, vapour pressures and enthalpies of sublimation, and enthalpies of formation of pyrazole, imidazole, indazole, and benzimidazole,
J. Chem. Thermodyn., 1987, 19, 985-992. [all data]
Guthrie and Pike, 1987
Guthrie, J.P.; Pike, D.C.,
Hydration of acylimidazoles: tetrahedral intermediates in acylimidazole hydrolysis and nucleophilic attack by imidazole on esters. The question of concerted mechanisms for acyl transfers,
Can. J. Chem., 1987, 65, 1951-1969. [all data]
Jimenez, Roux, et al., 1986
Jimenez, P.; Roux, M.V.; Turrion, C.; Gomis, F.,
Thermochemical properties of some N-heterocyclic compounds,
J. Calorim. Anal. Therm. Thermodyn. Chim., 1986, 17, 469-470. [all data]
Bedford, Edmondson, et al., 1962
Bedford, A.F.; Edmondson, P.B.; Mortimer, C.T.,
Heats of formation and bond energies. Part VI. n-Butyliso-butyraldimine, n-butylisobutylamine, pyrazole, and imidazole,
J. Chem. Soc., 1962, 2927-2931. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, References
- Symbols used in this document:
ΔfH°gas Enthalpy of formation of gas at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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