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)
  • UV/Visible spectrum
  • References
  • Notes
• Other data available:
  • Gas phase ion energetics data
  • Ion clustering data
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
• Options:
  • Switch to SI units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, "lite" edition (thermophysical and thermochemical data)
• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Condensed phase thermochemistry data

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

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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
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) (kcal/mol)
    T_r = reduced temperature (T / T_c)

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Antoine Equation Parameters

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

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Enthalpy of fusion

Entropy of fusion

Reaction thermochemistry data

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

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Mass spectrum (electron ionization), UV/Visible spectrum, References, Notes

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)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, UV/Visible spectrum, References, Notes

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

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Additional Data

UV/Visible spectrum

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

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Victor Talrose, Eugeny B. Stern, Antonina A. Goncharova, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

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), UV/Visible spectrum, 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]

Timmermans and Hennaut-Roland, 1955
Timmermans, J.; Hennaut-Roland, M., Work of the International Bureau of Physical-Chemical Standards. IX. The Physical Constants of Twenty Organic Compounds, J. Chim. Phys. Phys.-Chim. Biol., 1955, 52, 223. [all data]

Anonymous, 1942
Anonymous, R., , Am. Pet. Inst. Res. Proj. 6, Natl. Bur. Stand., 1942. [all data]

Milazzo, 1941
Milazzo, G., Boll. Sci. Facolta Chim. Ind. Bologna, 1941, 94. [all data]

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]

McCullough and Waddington, 1957
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]

Cumming and Kebarle, 1978
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]

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]

Larson and McMahon, 1987
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]

Payzant, Yamdagni, et al., 1971
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]

Larson and McMahon, 1983
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]

Arshadi, Yamdagni, et al., 1970
Arshadi, M.; Yamdagni, R.; Kebarle, P., Hydration of Halide Negative Ions in the Gas Phase. II. Comparison of Hydration Energies for the Alkali Positive and Halide Negative Ions, J. Phys. Chem., 1970, 74, 7, 1475, https://doi.org/10.1021/j100702a014 . [all data]

Larson and McMahon, 1984
Larson, J.W.; McMahon, T.B., Hydrogen bonding in gas phase anions. An experimental investigation of the interaction between chloride ion and bronsted acids from ICR chloride exchange equilibria, J. Am. Chem. Soc., 1984, 106, 517. [all data]

French, Ikuta, et al., 1982
French, M.A.; Ikuta, S.; Kebarle, P., Hydrogen bonding of O-H and C-H hydrogen donors to Cl^-. Results from mass spectrometric measurement of the ion-molecule equilibria RH + Cl^- = RHCl^-, Can. J. Chem., 1982, 60, 1907. [all data]

Meot-ner, 1988, 2
Meot-ner, M., The Ionic Hydrogen Bond and Solvation. 7. Interaction Energies of Carbanions with Solvent Molecules, J. Am. Chem. Soc., 1988, 110, 12, 3858, https://doi.org/10.1021/ja00220a022 . [all data]

Hiraoka, Takimoto, et al., 1987
Hiraoka, K.; Takimoto, H.; Yamabe, S., Stabilities and Structures in Cluster Ions of Five-Membered Heterocyclic Compounds Containing O, N and S Atoms, J. Am. Chem. Soc., 1987, 109, 24, 7346, https://doi.org/10.1021/ja00258a018 . [all data]

Deakyne and Meot-Ner (Mautner), 1985
Deakyne, C.A.; Meot-Ner (Mautner), M., Unconventional Ionic Hydrogen Bonds. 2. NH+ pi. Complexes of Onium Ions with Olefins and Benzene Derivatives, J. Am. Chem. Soc., 1985, 107, 2, 474, https://doi.org/10.1021/ja00288a034 . [all data]

Meot-Ner (Mautner), 1988
Meot-Ner (Mautner), M., Models for Strong Interactions in Proteins and Enzymes. 2. Interactions of Ions with the Peptide Link and Imidazole, J. Am. Chem. Soc., 1988, 110, 10, 3075, https://doi.org/10.1021/ja00218a014 . [all data]

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]

Huang and Rodgers, 2002
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), UV/Visible spectrum, 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
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.