1H-Indazole
- Formula: C7H6N2
- Molecular weight: 118.1359
- IUPAC Standard InChIKey: BAXOFTOLAUCFNW-UHFFFAOYSA-N
- CAS Registry Number: 271-44-3
- 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: Isoindazole; 1,2-Diazaindene; 1H-Benzopyrazole; 2-Azaindole; Indazole; Benzopyrazole
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Phase change data
Go To: Top, 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 as indicated in comments:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
AC - William E. Acree, Jr., James S. Chickos
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tfus | 419.3 | K | N/A | Rondestvedt and Blanchard, 1955 | Uncertainty assigned by TRC = 0.6 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 91.1 ± 0.2 | kJ/mol | V | Jimenez, Roux, et al., 1987 | see Jimenez, Roux, et al., 1986; ALS |
ΔsubH° | 91.1 | kJ/mol | N/A | Jimenez, Roux, et al., 1987 | DRB |
ΔsubH° | 91.1 ± 0.2 | kJ/mol | N/A | Jimenez, Roux, et al., 1987 | See also Jimenez, Roux, et al., 1986, 2.; AC |
ΔsubH° | 87.7 | kJ/mol | N/A | Faour and Akasheh, 1985 | DRB |
ΔsubH° | 97.1 | kJ/mol | V | Zimmerman and Geisenfelder, 1961 | ALS |
Reduced pressure boiling point
Tboil (K) | Pressure (bar) | Reference | Comment |
---|---|---|---|
543.2 | 0.991 | Aldrich Chemical Company Inc., 1990 | BS |
Enthalpy of sublimation
ΔsubH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
90.9 ± 0.2 | 318. | ME | Jimenez, Roux, et al., 1987 | Based on data from 308. to 317. K.; AC |
Gas phase ion energetics data
Go To: Top, Phase change data, 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) | 900.8 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 868.9 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.35 | PE | Kovac, Klasinc, et al., 1980 | LLK |
8.35 | PE | Kovac, Klasinc, et al., 1980 | Vertical value; LLK |
De-protonation reactions
C7H5N2- + =
By formula: C7H5N2- + H+ = C7H6N2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1457. ± 8.8 | kJ/mol | G+TS | Catalan, Claramunt, et al., 1988 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1425. ± 8.4 | kJ/mol | IMRE | Catalan, Claramunt, et al., 1988 | gas phase; B |
References
Go To: Top, Phase change 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.
Rondestvedt and Blanchard, 1955
Rondestvedt, C.S.; Blanchard, H.S.,
Arylation of Unsaturated Systems by Free Radicals I. Arylation of Alkylbenzenes,
J. Am. Chem. Soc., 1955, 77, 1769. [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]
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]
Jimenez, Roux, et al., 1986, 2
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. [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]
Zimmerman and Geisenfelder, 1961
Zimmerman, H.; Geisenfelder, H.,
Uber die Mesomerieenergie von Azolen,
Z. Electrochem., 1961, 65, 368-371. [all data]
Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc.,
Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [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]
Catalan, Claramunt, et al., 1988
Catalan, J.; Claramunt, R.M.; Elguero, J.; Menedez, M.; Anvia, F.; Quian, J.H.; Taagepera, M.; Taft, R.W.,
Basicity and Acidity of Azoles. The Annelation Effect in Azoles.,
J. Am. Chem. Soc., 1988, 110, 13, 4107, https://doi.org/10.1021/ja00221a001
. [all data]
Notes
Go To: Top, Phase change data, Gas phase ion energetics data, References
- Symbols used in this document:
Tboil Boiling point Tfus Fusion (melting) point ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions 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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