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
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
• Options:
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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)

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
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

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

 +  =

By formula: C₄H₄N^- + H⁺ = C₄H₅N

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.

Zaheeruddin and Lodhi, 1991
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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]

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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]

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Muftakhov, Vasil'ev, et al., 1999
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Meot-ner, 1988
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Larson, J.W.; McMahon, T.B., Hydrogen bonding in gas phase anions. The energetics of interaction between cyanide ion and bronsted acids, J. Am. Chem. Soc., 1987, 109, 6230. [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 and Yang, 2000
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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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:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  IE (evaluated)	Recommended ionization energy
  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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