Pyrrole

• Formula: C₄H₅N
• Molecular weight: 67.0892
• IUPAC Standard InChI: InChI=1S/C4H5N/c1-2-4-5-3-1/h1-5H Copy

  
• IUPAC Standard InChIKey: KAESVJOAVNADME-UHFFFAOYSA-N Copy
• CAS Registry Number: 109-97-7
• 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-Pyrrole; Azole; Divinylenimine; Imidole; Monopyrrole; Pyrrol; 1-Aza-2,4-cyclopentadiene; Divinyleneimine; Parzate; NSC 62777
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas phase ion energetics data
  • Ion clustering data
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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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 as indicated in comments:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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

Constant pressure heat capacity of liquid

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
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of vaporization

Enthalpy of vaporization

Δ_vapH = A exp(-βT_r) (1 − T_r)^β
    Δ_vapH = Enthalpy of vaporization (at saturation pressure) (kJ/mol)
    T_r = reduced temperature (T / T_c)

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Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

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Enthalpy of fusion

Entropy of fusion

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
RCD - Robert C. Dunbar

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

 +  =

By formula: C₄H₄N^- + H⁺ = C₄H₅N

CN^- +  = (CN^- • )

By formula: CN^- + C₄H₅N = (CN^- • C₄H₅N)

 +  = ( • )

By formula: F^- + C₄H₅N = (F^- • C₄H₅N)

 +  = ( • )

By formula: Cl^- + C₄H₅N = (Cl^- • C₄H₅N)

Free energy of reaction

HS^- +  = (HS^- • )

By formula: HS^- + C₄H₅N = (HS^- • C₄H₅N)

 +  = ( • )

By formula: C₄H₄N^- + C₄H₅N = (C₄H₄N^- • C₄H₅N)

 +  = ( • )

By formula: C₂H₃O₂^- + C₄H₅N = (C₂H₃O₂^- • C₄H₅N)

(C₄H₅N⁺ • ) +  = (C₄H₅N⁺ • 2)

By formula: (C₄H₅N⁺ • C₄H₅N) + C₄H₅N = (C₄H₅N⁺ • 2C₄H₅N)

Bond type: Charge transfer bond (positive ion)

C₄H₅N⁺ +  = (C₄H₅N⁺ • )

By formula: C₄H₅N⁺ + C₄H₅N = (C₄H₅N⁺ • C₄H₅N)

Bond type: Charge transfer bond (positive ion)

(C₄H₆N⁺ • ) +  = (C₄H₆N⁺ • 2)

By formula: (C₄H₆N⁺ • C₄H₅N) + C₄H₅N = (C₄H₆N⁺ • 2C₄H₅N)

( • ) +  = ( • 2)

By formula: (C₄H₄N^- • C₄H₅N) + C₄H₅N = (C₄H₄N^- • 2C₄H₅N)

C₄H₆N⁺ +  = (C₄H₆N⁺ • )

By formula: C₄H₆N⁺ + C₄H₅N = (C₄H₆N⁺ • C₄H₅N)

( • ) +  = ( • 2)

By formula: (C₂H₃O₂^- • C₄H₅N) + C₄H₅N = (C₂H₃O₂^- • 2C₄H₅N)

CH₆N⁺ +  = (CH₆N⁺ • )

By formula: CH₆N⁺ + C₄H₅N = (CH₆N⁺ • C₄H₅N)

 +  = ( • )

By formula: C₆H₁₁NO₃ + C₄H₅N = (C₆H₁₁NO₃ • C₄H₅N)

( • ) +  = ( • 2)

By formula: (Fe⁺ • C₄H₅N) + C₄H₅N = (Fe⁺ • 2C₄H₅N)

( • ) +  = ( • 2)

By formula: (Cr⁺ • C₄H₅N) + C₄H₅N = (Cr⁺ • 2C₄H₅N)

( • ) +  = ( • 2)

By formula: (Mn⁺ • C₄H₅N) + C₄H₅N = (Mn⁺ • 2C₄H₅N)

( • ) +  = ( • 2)

By formula: (Ni⁺ • C₄H₅N) + C₄H₅N = (Ni⁺ • 2C₄H₅N)

( • ) +  = ( • 2)

By formula: (Co⁺ • C₄H₅N) + C₄H₅N = (Co⁺ • 2C₄H₅N)

( • ) +  = ( • 2)

By formula: (Cu⁺ • C₄H₅N) + C₄H₅N = (Cu⁺ • 2C₄H₅N)

 +  = ( • )

By formula: Li⁺ + C₄H₅N = (Li⁺ • C₄H₅N)

 +  = ( • )

By formula: Na⁺ + C₄H₅N = (Na⁺ • C₄H₅N)

 +  = ( • )

By formula: K⁺ + C₄H₅N = (K⁺ • C₄H₅N)

 +  = ( • )

By formula: V⁺ + C₄H₅N = (V⁺ • C₄H₅N)

 +  = ( • )

By formula: Ni⁺ + C₄H₅N = (Ni⁺ • C₄H₅N)

 +  = ( • )

By formula: W⁺ + C₄H₅N = (W⁺ • C₄H₅N)

 +  = ( • )

By formula: Co⁺ + C₄H₅N = (Co⁺ • C₄H₅N)

 +  = ( • )

By formula: Mo⁺ + C₄H₅N = (Mo⁺ • C₄H₅N)

 +  = ( • )

By formula: Fe⁺ + C₄H₅N = (Fe⁺ • C₄H₅N)

 +  = ( • )

By formula: Cr⁺ + C₄H₅N = (Cr⁺ • C₄H₅N)

 +  = ( • )

By formula: Mn⁺ + C₄H₅N = (Mn⁺ • C₄H₅N)

 +  = ( • )

By formula: Mg⁺ + C₄H₅N = (Mg⁺ • C₄H₅N)

 +  = ( • )

By formula: Al⁺ + C₄H₅N = (Al⁺ • C₄H₅N)

 +  = ( • )

By formula: Cu⁺ + C₄H₅N = (Cu⁺ • C₄H₅N)

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• Not specified, most likely a prism, grating, or hybrid spectrometer.; (NO SPECTRUM, ONLY SCANNED IMAGE IS AVAILABLE)

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

• gas

Mass spectrum (electron ionization)

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), 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]

Scott, Berg, et al., 1967
Scott, D.W.; Berg, W.T.; Hossenlopp, I.A.; Hubbard, W.N.; Messerly, J.F.; Todd, S.S.; Douslin, D.R.; McCullough, J.P.; Waddington, G., Pyrrole: Chemical thermodynamic properties, J. Phys. Chem., 1967, 71, 2263-2270. [all data]

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

Rosso and Carbonnel, 1973
Rosso, M.J.-C.; Carbonnel, L., Hydrates + cubic clathrates generated by the nitrogenous meterocycles: the binary systems water + propylene imine and water + pyrrole, C. R. Seances Acad. Sci., Ser. C, 1973, 277, 259. [all data]

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Scott, Berg, et al., 1967, 2
Scott, D.W.; Berg, W.T.; Hossenlopp, I.A.; Hubbard, W.N.; Messerly, J.F.; Todd, S.S.; Douslin, D.R.; McCullough, J.P.; Waddington, G., Pyrrole: Chemical Thermodynamic Properties, J. Phys. Chem., 1967, 71, 2263. [all data]

Helm, Lanum, et al., 1958
Helm, R.V.; Lanum, W.J.; Cook, G.L.; Ball, J.S., Purification and Properties of Pyrrole, Pyrrolidine, Pyridine and 2-Methylpyridine, J. Phys. Chem., 1958, 62, 858. [all data]

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McCullough, J.P.; Waddington, G., Melting-point purity determinations: limitations as evidenced by calorimetric studies in the melting region, Anal. Chim. Acta, 1957, 17, 80. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

Cheng, McCoubrey, et al., 1962
Cheng, D.C.H.; McCoubrey, J.C.; Phillips, D.G., Critical Temperatures of Some Organic Cyclic Compounds, Trans. Faraday Soc., 1962, 58, 224. [all data]

Glaser and Ruland, 1957
Glaser, F.; Ruland, H., Untersuchungsen über dampfdruckkurven und kritische daten einiger technisch wichtiger organischer substanzen, Chem. Ing. Techn., 1957, 29, 772. [all data]

Kimizuka and Szydlowski, 1992
Kimizuka, Wieslawa; Szydlowski, Jerzy, Vapor pressure isotope effect of n-deuterated pyrrole, Fluid Phase Equilibria, 1992, 77, 261-267, https://doi.org/10.1016/0378-3812(92)85107-J . [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Osborn and Douslin, 1968
Osborn, Ann G.; Douslin, Donald R., Vapor pressure relations of 13 nitrogen compounds related to petroleum, J. Chem. Eng. Data, 1968, 13, 4, 534-537, https://doi.org/10.1021/je60039a024 . [all data]

Eon, Pommier, et al., 1971
Eon, C.; Pommier, C.; Guiochon, G., Vapor pressures and second virial coefficients of some five-membered heterocyclic derivatives, J. Chem. Eng. Data, 1971, 16, 4, 408-410, https://doi.org/10.1021/je60051a008 . [all data]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [all data]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [all data]

Gianola, Ichino, et al., 2004
Gianola, A.J.; Ichino, T.; Hoenigman, R.L.; Kato, S.; Bierbaum, V.M.; Lineberger, W.C., Thermochemistry and electronic structure of the pyrrolyl radical, J. Phys. Chem. A, 2004, 108, 46, 10326-10335, https://doi.org/10.1021/jp047790+ . [all data]

Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr., The gas phase acidity scale from methanol to phenol, J. Am. Chem. Soc., 1979, 101, 6047. [all data]

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Cumming, J.B.; Kebarle, P., Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A), Can. J. Chem., 1978, 56, 1. [all data]

Muftakhov, Vasil'ev, et al., 1999
Muftakhov, M.V.; Vasil'ev, Y.V.; Khatymov, R.V.; Mazunov, V.A.; Takhistov, V.V.; Travkin, O.V.; Yakovleva, E.V., Thermochemistry of negatively charged ions. II. Energetics of formation of negative ions from acridanone and some of its derivatives, Rapid Commun. Mass Spectrom., 1999, 13, 10, 912-923, https://doi.org/10.1002/(SICI)1097-0231(19990530)13:10<912::AID-RCM585>3.0.CO;2-W . [all data]

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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]

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Payzant, J.D.; Yamdagni, R.; Kebarle, P., Hydration of CN-, NO₂-, NO₃-, and HO- in the gas phase, Can. J. Chem., 1971, 49, 3308. [all data]

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Larson, J.W.; McMahon, T.B., Strong hydrogen bonding in gas-phase anions. An ion cyclotron resonance determination of fluoride binding energetics to bronsted acids from gas-phase fluoride exchange equilibria measurements, J. Am. Chem. Soc., 1983, 105, 2944. [all data]

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Gapeev, A.; Yang, C.-N., Binding Energies of Gas-Phase Ions with Pyrrole. Experimental and Quantum Chemical Results, J. Phys. Chem. A, 2000, 104, 14, 3246, https://doi.org/10.1021/jp992627d . [all data]

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Huang, H.; Rodgers, M.T., Sigma versus Pi interactions in alkali metal ion binding to azoles: Threshold collision-induced dissociation and ab initio theory studies, J. Phys. Chem. A, 2002, 106, 16, 4277, https://doi.org/10.1021/jp013630b . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  Cp,liquid	Constant pressure heat capacity of liquid
  Pc	Critical pressure
  S°liquid	Entropy of liquid at standard conditions
  T	Temperature
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

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