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
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• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Ion clustering data
  • IR Spectrum
  • 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

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

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
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

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, Phase change data, Gas phase ion energetics data, 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]

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]

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]

Klasinc, Sabljic, et al., 1982
Klasinc, L.; Sabljic, A.; Kluge, G.; Rieger, J.; Scholz, M., Chemistry of excited states. Part 13. Assignment of lowest .PI.-ionizations in photoelectron spectra of thiophen, furan, and pyrrole, J. Chem. Soc. Perkin Trans. 2, 1982, 539. [all data]

Galasso, Klasinc, et al., 1981
Galasso, V.; Klasinc, L.; Sabluic, A.; Trinajstic, N.; Pappalardo, G.C.; Steglich, W., Conformation and photoelectron spectra of 2-(2-Furyl)pyrrole and 2-(2-tThienyl)pyrrole, J. Chem. Soc. Perkin Trans. 2, 1981, 127. [all data]

Willett and Baer, 1980
Willett, G.D.; Baer, T., Thermochemistry and dissociation dynamics of state-selected C₄H₄X ions. 3. C₄H₅N⁺, J. Am. Chem. Soc., 1980, 102, 6774. [all data]

Tedder and Vidaud, 1980
Tedder, J.M.; Vidaud, P.H., Charge exchange mass spectra of thiophene, pyrrole and furan, J. Chem. Soc. Faraday Trans. 2, 1980, 76, 1516. [all data]

Cooper, Williamson, et al., 1980
Cooper, C.D.; Williamson, A.D.; Miller, J.C.; Compton, R.N., Resonantly enhanced multiphoton ionization of pyrrole, N-methyl pyrrole, and furan, J. Chem. Phys., 1980, 73, 1527. [all data]

Williamson, Compton, et al., 1979
Williamson, A.D.; Compton, R.N.; Eland, J.H.D., Accurate photoionization thresholds by multiphoton ionization: Pyrrole, J. Chem. Phys., 1979, 70, 590. [all data]

Van Veen, 1976
Van Veen, E.H., Triplet π-π^* transitions in thiophene, furan and pyrrole by low-energy electron-impact spectroscopy, Chem. Phys. Lett., 1976, 41, 535. [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]

Linda, Marino, et al., 1971
Linda, P.; Marino, G.; Pignataro, S., A comparison of sensitivities to substituent effects of five- membered heteroaromatic rings in gas phase ionization, J. Chem. Soc. B, 1971, 1585. [all data]

Derrick, Asbrink, et al., 1971
Derrick, P.J.; Asbrink, L.; Edqvist, O.; Jonsson, B.-O.; Lindholm, E., Rydberg series in small molecules. XII. Photoelectron spectroscopy and electronic structure of pyrrole, Intern. J. Mass Spectrom. Ion Phys., 1971, 6, 191. [all data]

Potapov and Yuzhakova, 1970
Potapov, V.K.; Yuzhakova, O.A., Photoionization and electronic structure of pyrrole and its methyl derivatives, Dokl. Akad. Nauk SSSR, 1970, 192, 131, In original 365. [all data]

Potapov and Bazhenov, 1970
Potapov, V.K.; Bazhenov, B.A., The photionization of pyrrole, furan, and thiophene, High Energy Chem., 1970, 505, In original 553. [all data]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

Cradock, Findlay, et al., 1973
Cradock, S.; Findlay, R.H.; Palmer, M.H., The molecular energy levels of the azoles: A study by photoelectron spectroscopy and ab initio molecular orbital calculations, Tetrahedron, 1973, 29, 2173. [all data]

Sakurai and Jennings, 1981
Sakurai, H.; Jennings, K.R., A study of the structures of decomposing and non-decomposing [C₄H₅N]⁺ ions formed from different neutral species, Org. Mass Spectrom., 1981, 16, 393. [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]

Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  Pc	Critical pressure
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔfH°gas	Enthalpy of formation of gas 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
  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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