Indole

• Formula: C₈H₇N
• Molecular weight: 117.1479
• IUPAC Standard InChI: InChI=1S/C8H7N/c1-2-4-8-7(3-1)5-6-9-8/h1-6,9H Copy

  
• IUPAC Standard InChIKey: SIKJAQJRHWYJAI-UHFFFAOYSA-N Copy
• CAS Registry Number: 120-72-9
• 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: 1H-Indole; Ketole; 1-Azaindene; 1-Benzazole; 2,3-Benzopyrrole; Benzopyrrole; Indol; 1-H-indol
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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 as indicated in comments:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

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

C₈H₆N^- +  =

By formula: C₈H₆N^- + H⁺ = C₈H₇N

 +  = ( • )

By formula: C₂H₃O₂^- + C₈H₇N = (C₂H₃O₂^- • C₈H₇N)

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
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

View reactions leading to C₈H₇N⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

De-protonation reactions

C₈H₆N^- +  =

By formula: C₈H₆N^- + H⁺ = C₈H₇N

References

Go To: Top, Condensed phase thermochemistry 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.

Good, 1972
Good, W.D., Enthalpies of combustion of nine organic nitrogen compounds related to petroleum, J. Chem. Eng. Data, 1972, 17, 28-31. [all data]

Zimmerman and Geisenfelder, 1961
Zimmerman, H.; Geisenfelder, H., Uber die Mesomerieenergie von Azolen, Z. Electrochem., 1961, 65, 368-371. [all data]

Stern and Klebs, 1933
Stern, A.; Klebs, G., Calorimetrische Bestimmungen bei einfachen und mehrkernigen Pyrrolderivaten, Ann., 1933, 504, 287-297. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Meot-ner, Liebman, et al., 1988
Meot-ner, M.; Liebman, J.F.; Kafafi, S.A., Ionic Probes of Aromaticity in Annelated Rings, J. Am. Chem. Soc., 1988, 110, 18, 5937, https://doi.org/10.1021/ja00226a001 . [all data]

Kiefer, Zhang, et al., 1997
Kiefer, J.H.; Zhang, Q.; Kern, R.D.; Yao, J.; Jursic, B., Pyrolysis of Aromatic Azines: Pyrazine, Pyrimidine, and Pyridine, J. Phys. Chem. A, 1997, 101, 38, 7061, https://doi.org/10.1021/jp970211z . [all data]

Taft and Bordwell, 1988
Taft, R.W.; Bordwell, F.G., Structural and Solvent Effects Evaluated from Acidities Measured in Dimethyl Sulfoxide and in the Gas Phase, Acc. Chem. Res., 1988, 21, 12, 463, https://doi.org/10.1021/ar00156a005 . [all data]

Meot-ner, 1988
Meot-ner, M., Ionic Hydrogen Bond and Ion Solvation. ₆. Interaction Energies of the Acetate Ion with Organic Molecules. Comparison of CH₃COO^- with Cl^-, CN^-, and SH^-, J. Am. Chem. Soc., 1988, 110, 12, 3854, https://doi.org/10.1021/ja00220a022 . [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]

Carles, Desfrancois, et al., 2000
Carles, S.; Desfrancois, C.; Schermann, J.P.; Smith, D.M.A.; Adamowicz, L., Structures and electron affinities of indole-(water)(N) clusters, J. Chem. Phys., 2000, 112, 8, 3726-3734, https://doi.org/10.1063/1.480938 . [all data]

Hager and Wallace, 1988
Hager, J.W.; Wallace, S.C., Two-laser photoionization supersonic jet mass spectrometry of aromatic molecules, Anal. Chem., 1988, 60, 5. [all data]

Hager, Ivanco, et al., 1985
Hager, J.; Ivanco, M.; Smith, M.A.; Wallace, S.C., Solvation effects in jet-cooled Van der Waals Clusters: Two-color threshold photoionization spectroscopy of indole, indole-argon, indole-methane, indole-water and indole-methanol, Chem. Phys. Lett., 1985, 113, 503. [all data]

Corval, 1979
Corval, M., Elimination sous impact electronique de HCN et H a partir de l'Indole. Comparaison avec l'Indolizine, Org. Mass Spectrom., 1979, 14, 213. [all data]

Thorstad and Undheim, 1974
Thorstad, O.; Undheim, K., Mass spectrometry of onium compounds. XXIV. Ionisation potential in structure analysis of pyridodiazo-oxides, Chem. Scr., 1974, 6, 222. [all data]

Dewar, Harget, et al., 1970
Dewar, M.J.S.; Harget, A.J.; Trinajstic, N.; Worley, S.D., Ground states of conjugated molecules-XXI.Benzofurans and benzopyrroles, Tetrahedron, 1970, 26, 4505. [all data]

Eland, 1969
Eland, J.H.D., Photoelectron spectra of conjugated hydrocarbons and heteromolecules, Intern. J. Mass Spectrom. Ion Phys., 1969, 2, 471. [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]

Domelsmith, Munchausen, et al., 1977
Domelsmith, L.N.; Munchausen, L.L.; Houk, K.N., Photoelectron spectra of psychotropic drugs. 1. Phenethylamines, tryptamines, and LSD, J. Am. Chem. Soc., 1977, 99, 4311. [all data]

Gusten, Klasinc, et al., 1976
Gusten, H.; Klasinc, L.; Ruscic, B., Photoelectron spectroscopy of J. Heterocycl. Chem.. Indene analogs, Z. Naturforsch. A:, 1976, 31, 1051. [all data]

Dolby, Hanson, et al., 1976
Dolby, L.J.; Hanson, G.; Koenig, T., The He I photoelectron spectra of N-methylisoindole and N-methylindole, J. Org. Chem., 1976, 41, 3537. [all data]

Notes

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• Symbols used in this document:
  

  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  ΔcH°solid	Enthalpy of combustion of solid 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
  ΔrS°	Entropy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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