1H-Benzimidazole
- Formula: C7H6N2
- Molecular weight: 118.1359
- IUPAC Standard InChIKey: HYZJCKYKOHLVJF-UHFFFAOYSA-N
- CAS Registry Number: 51-17-2
- 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: Benzimidazole; o-Benzimidazole; Azindole; Benziminazole; Benzoglyoxaline; Benzoimidazole; BZI; N,N'-Methenyl-o-phenylenediamine; 1,3-Benzodiazole; 1,3-Diazaindene; 3-Azaindole; NSC 759
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Phase change 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:
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔsubH° | 101. ± 7. | kJ/mol | AVG | N/A | Average of 6 values; Individual data points |
Enthalpy of sublimation
ΔsubH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
90.2 ± 0.6 | 363. | C | Lehman, Gentry, et al., 1998 | AC |
101.8 ± 0.4 | 350. | ME | Jimenez, Roux, et al., 1987 | Based on data from 340. to 359. K.; AC |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
20.47 | 445.5 | Domanska, Kozlowska, et al., 2002 | AC |
19.25 | 443.2 | Pitzer, Peiper, et al., 1984 | AC |
Gas phase ion energetics data
Go To: Top, Phase change 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:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Proton affinity (review) | 953.8 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 920.5 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.0 | PE | Kovac, Klasinc, et al., 1980 | LLK |
8.0 | PE | Ramsey, 1979 | LLK |
8.45 | PE | Kovac, Klasinc, et al., 1980 | Vertical value; LLK |
8.44 | PE | Ramsey, 1979 | Vertical value; LLK |
Gas Chromatography
Go To: Top, Phase change 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
Normal alkane RI, polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | FFAP | 2039. | Nebesny, Budryn, et al., 2007 | 30. m/0.32 mm/0.5 μm, N2, 35. C @ 5. min, 4. K/min, 320. C @ 45. min |
References
Go To: Top, Phase change 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.
Lehman, Gentry, et al., 1998
Lehman, Richard L.; Gentry, Jefffery S.; Glumac, Nick G.,
Thermal stability of potassium carbonate near its melting point,
Thermochimica Acta, 1998, 316, 1, 1-9, https://doi.org/10.1016/S0040-6031(98)00289-5
. [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]
Domanska, Kozlowska, et al., 2002
Domanska, Urszula; Kozlowska, Marta Karolina; Rogalski, Marek,
Solubilities, Partition Coefficients, Density, and Surface Tension for Imidazoles + Octan-1-ol or + Water or + n -Decane «8224»,
J. Chem. Eng. Data, 2002, 47, 3, 456-466, https://doi.org/10.1021/je0103014
. [all data]
Pitzer, Peiper, et al., 1984
Pitzer, Kenneth S.; Peiper, J. Christopher; Busey, R.H.,
Thermodynamic Properties of Aqueous Sodium Chloride Solutions,
J. Phys. Chem. Ref. Data, 1984, 13, 1, 1, https://doi.org/10.1063/1.555709
. [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]
Kovac, Klasinc, et al., 1980
Kovac, B.; Klasinc, L.; Stanovnik, B.; Tisler, M.,
Photoelectron spectroscopy of J. Heterocycl. Chem.. Azaindenes azaindolizines (1),
J. Heterocycl. Chem., 1980, 17, 689. [all data]
Ramsey, 1979
Ramsey, B.G.,
Substituent effects on imidazole basicity and photoelectron spectroscopy determined ionization energies,
J. Org. Chem., 1979, 44, 2093. [all data]
Nebesny, Budryn, et al., 2007
Nebesny, E.; Budryn, G.; Kula, J.; Majda, T.,
The effect of roasting method on headspace composition of robusta coffee bean aroma,
Eur. Food Res. Technol., 2007, 225, 1, 9-19, https://doi.org/10.1007/s00217-006-0375-0
. [all data]
Notes
Go To: Top, Phase change data, Gas phase ion energetics data, Gas Chromatography, References
- Symbols used in this document:
ΔfusH Enthalpy of fusion ΔsubH Enthalpy of sublimation ΔsubH° Enthalpy of sublimation at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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