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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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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | 243.0 ± 1.3 | kJ/mol | Ccb | Jimenez, Roux, et al., 1987 | see Jimenez, Roux, et al., 1986 |
ΔfH°gas | 254.2 ± 4.6 | kJ/mol | Ccb | Faour and Akasheh, 1985 |
Condensed 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
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°solid | 151.9 ± 1.3 | kJ/mol | Ccb | Jimenez, Roux, et al., 1987 | see Jimenez, Roux, et al., 1986; ALS |
ΔfH°solid | 166.5 ± 3.7 | kJ/mol | Ccb | Faour and Akasheh, 1985 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°solid | -3764.0 ± 0.9 | kJ/mol | Ccb | Jimenez, Roux, et al., 1987 | see Jimenez, Roux, et al., 1986; ALS |
ΔcH°solid | -3778.6 ± 3.5 | kJ/mol | Ccb | Faour and Akasheh, 1985 | ALS |
ΔcH°solid | -3764. | kJ/mol | Ccb | Zimmerman and Geisenfelder, 1961 | ALS |
Constant pressure heat capacity of solid
Cp,solid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
128.8 | 298.15 | Jimenez, Roux, et al., 1987 | Cp given as 1.09 J K-1 g-1.; DH |
Phase change 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:
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 |
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 by: John E. Bartmess
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
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 |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1425. ± 8.4 | kJ/mol | IMRE | Catalan, Claramunt, et al., 1988 | gas phase |
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
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, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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.
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]
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]
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., 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]
Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc.,
Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [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]
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]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
Cp,solid Constant pressure heat capacity of solid Tboil Boiling point Tfus Fusion (melting) point ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°solid Enthalpy of formation of solid at standard conditions 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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