Pyrrolidine

• Formula: C₄H₉N
• Molecular weight: 71.1210
• IUPAC Standard InChI: InChI=1S/C4H9N/c1-2-4-5-3-1/h5H,1-4H2 Copy

  
• IUPAC Standard InChIKey: RWRDLPDLKQPQOW-UHFFFAOYSA-N Copy
• CAS Registry Number: 123-75-1
• 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: Azacyclopentane; Azolidine; Butylenimine; Prolamine; Pyrrole, tetrahydro-; Tetrahydropyrrole; Tetramethylenimine; Perhydropyrrole; UN 1922; NSC 62781; Pyrrolidine ring
• 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
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Henry's Law data
  • IR Spectrum
• 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 by: 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
CAL - James S. Chickos, William E. Acree, Jr., Joel F. Liebman, Students of Chem 202 (Introduction to the Literature of Chemistry), University of Missouri -- St. Louis
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

Enthalpy of phase transition

Entropy of phase transition

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:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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

(C₄H₁₀N⁺ • ) +  = (C₄H₁₀N⁺ • 2)

By formula: (C₄H₁₀N⁺ • C₄H₉N) + C₄H₉N = (C₄H₁₀N⁺ • 2C₄H₉N)

C₄H₁₀N⁺ +  = (C₄H₁₀N⁺ • )

By formula: C₄H₁₀N⁺ + C₄H₉N = (C₄H₁₀N⁺ • C₄H₉N)

3 +  = 3

By formula: 3H₂ + C₁₂H₂₁N₃ = 3C₄H₉N

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

Data compiled as indicated in comments:
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

Ion clustering 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: 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. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

C₄H₁₀N⁺ +  = (C₄H₁₀N⁺ • )

By formula: C₄H₁₀N⁺ + C₄H₉N = (C₄H₁₀N⁺ • C₄H₉N)

(C₄H₁₀N⁺ • ) +  = (C₄H₁₀N⁺ • 2)

By formula: (C₄H₁₀N⁺ • C₄H₉N) + C₄H₉N = (C₄H₁₀N⁺ • 2C₄H₉N)

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

UV/Visible spectrum

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

Spectrum

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Additional Data

Gas Chromatography

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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

Kovats' RI, non-polar column, isothermal

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Kovats' RI, non-polar column, custom temperature program

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Kovats' RI, polar column, isothermal

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Van Den Dool and Kratz RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, custom temperature program

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Normal alkane RI, polar column, temperature ramp

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Normal alkane RI, polar column, custom temperature program

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References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), UV/Visible spectrum, Gas Chromatography, Notes

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

Hildenbrand, Sinke, et al., 1959
Hildenbrand, D.L.; Sinke, G.C.; McDonald, R.A.; Kramer, W.R.; Stull, D.R., Thermodynamic and spectroscopic study of pyrrolidine. I. Thermodynamic properties in the solid, liquid, and vapor states, J. Chem. Phys., 1959, 31, 650-654. [all data]

McCullough, Douslin, et al., 1959
McCullough, J.P.; Douslin, D.R.; Hubbard, W.N.; Todd, S.S.; Messerly, J.F.; Hossenlopp, I.A.; Frow, F.R.; Dawson, J.P.; Waddington, G., Pyrrolidine: Chemical thermodynamic properties between 0 and 1500°K; effect of pseudorotation; and an unusual thermal anomaly in the liquid state, J. Am. Chem. Soc., 1959, 81, 5884-5890. [all data]

Conti, Gianni, et al., 1976
Conti, G.; Gianni, P.; Matteoli, E.; Mengheri, M., Capacita termiche molari di alcuni composti organici mono- e bifunzionali nel liquido puro e in soluzione acquosa a 25C, Chim. Ind. (Milan), 1976, 58, 225. [all data]

Boord, Greenlee, et al., 1950
Boord, C.E.; Greenlee, K.W.; Derfer, J.M., The Synthesis, Purification and Prop. of Hydrocarbons of Low Mol. Wt., Am. Pet. Inst. Res. Proj. 45, Twelfth Annu. Rep., Ohio State Univ., 1950. [all data]

Hildenbrand, Sinke, et al., 1959, 2
Hildenbrand, D.L.; Sinke, G.C.; McDonald, R.A.; Kramer, W.R.; Stull, D.R., Thermodynamic and Spectroscopic Study of Pyrrolidine. I. Thermodynamic Properties in the Solid, Liquid, and Vapor States, J. Chem. Phys., 1959, 31, 3, 650, https://doi.org/10.1063/1.1730441 . [all data]

McCullough, Douslin, et al., 1959, 2
McCullough, J.P.; Douslin, D.R.; Hubbard, W.N.; Todd, S.S.; Messerly, J.F.; Hossenlopp, I.A.; Frow, F.R.; Dawson, J.P.; Waddington, G., Pyrrolidine: Chemical Thermodynamic Properties Between 0 and 1500 K; Effect of Pseudorotation; and an Unusual Thermal Anomaly in the Liquid State, J. Am. Chem. Soc., 1959, 81, 5884-90. [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]

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]

Kobe, Ravicz, et al., 1956
Kobe, K.A.; Ravicz, A.E.; Vohra, S.P., Critical Properties and Vapor Pressures of Some Ethers and Heterocyclic Compounds, J. Chem. Eng. Data, 1956, 1, 50. [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]

Boublik, Fried, et al., 1984
Boublik, T.; Fried, V.; Hala, E., The Vapour Pressures of Pure Substances: Selected Values of the Temperature Dependence of the Vapour Pressures of Some Pure Substances in the Normal and Low Pressure Region, 2nd ed., Elsevier, New York, 1984, 972. [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]

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]

Wiberg, Nakaji, et al., 1993
Wiberg, K.B.; Nakaji, D.Y.; Morgan, K.M., Heat of hydrogenation of a cis imine. An experimental and theoretical study, J. Am. Chem. Soc., 1993, 115, 3527-3532. [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]

Al-Joboury and Turner, 1964
Al-Joboury, M.I.; Turner, D.W., Molecular photoelectron spectroscopy. Part II. A summary of ionization potentials, J. Chem. Soc., 1964, 4434. [all data]

Gerson, Worley, et al., 1978
Gerson, S.H.; Worley, S.D.; Bodor, N.; Kaminski, J.J.; Flechtner, T.W., The photoelectron spectra of some heterocyclic compounds which contain N, O, Cl, and Br, J. Electron Spectrosc. Relat. Phenom., 1978, 13, 421. [all data]

Aue, Webb, et al., 1976
Aue, D.H.; Webb, H.M.; Bowers, M.T., Quantitative proton affinities, ionization potentials, and hydrogen affinities of alkylamines, J. Am. Chem. Soc., 1976, 98, 311. [all data]

Morishima, Yoshikawa, et al., 1975
Morishima, I.; Yoshikawa, K.; Hashimoto, M.; Bekki, K., Homoallylic interaction between the nitrogen lone pair and the nonadjacent π bond in cyclic and bicyclic amines. I. Photoelectron spectroscopic study, J. Am. Chem. Soc., 1975, 97, 4283. [all data]

Colonna, Distefano, et al., 1975
Colonna, F.P.; Distefano, G.; Pignataro, S.; Pitacco, G.; Valentin, E., Ionization energies of some amines and enamines and an estimation of their relative basicity in gaseous phase, J. Chem. Soc. Faraday Trans. 2, 1975, 71, 1572. [all data]

Yoshikawa, Hashimoto, et al., 1974
Yoshikawa, K.; Hashimoto, M.; Morishima, I., Photoelectron spectroscopic study of cyclic amines. The relation between ionization potentials, basicities, and s character of the nitrogen lone pair electrons, J. Am. Chem. Soc., 1974, 96, 288. [all data]

Gallegos and Kiser, 1962
Gallegos, E.J.; Kiser, R.W., Electron impact spectroscopy of the four- and five-membered, saturated heterocyclic compounds containing nitrogen, oxygen and sulfur, J. Phys. Chem., 1962, 66, 136. [all data]

Pickett, Corning, et al., 1953
Pickett, L.W.; Corning, M.E.; Wieder, G.M.; Semenow, D.A.; Buckley, J.M., The vacuum ultraviolet spectra of cyclic compounds. III. Amines, J. Am. Chem. Soc., 1953, 75, 1618-1622. [all data]

Zhuravleva, 2000
Zhuravleva, I.L., Evaluation of the polarity and boiling points of nitrogen-containing heterocyclic compounds by gas chromatography, Russ. Chem. Bull. (Engl. Transl.), 2000, 49, 2, 325-328, https://doi.org/10.1007/BF02494682 . [all data]

Reddy, Dutoit, et al., 1992
Reddy, K.S.; Dutoit, J.-Cl.; Kovats, E. sz., Pair-wise interactions by gas chromatography. I. Interaction free enthalpies of solutes with non-associated primary alcohol groups, J. Chromatogr., 1992, 609, 1-2, 229-259, https://doi.org/10.1016/0021-9673(92)80167-S . [all data]

Dutoit, 1991
Dutoit, J., Gas chromatographic retention behaviour of some solutes on structurally similar polar and non-polar stationary phases, J. Chromatogr., 1991, 555, 1-2, 191-204, https://doi.org/10.1016/S0021-9673(01)87179-X . [all data]

Zhuravleva, Kapustin, et al., 1976
Zhuravleva, I.L.; Kapustin, Yu.P.; Golovnya, P.B., Retention indices of some isoaliphatic and heterocyclic nitrogenous bases, Zh. Anal. Khim., 1976, 31, 1378-1380. [all data]

Anderson, Jurel, et al., 1973
Anderson, A.; Jurel, S.; Shymanska, M.; Golender, L., Gas-liquid chromatography of some aliphatic and heterocyclic mono- and pollyfunctional amines. VII. Retention indices of amines in some polar and unpolar stationary phases, Latv. PSR Zinat. Akad. Vestis Kim. Ser., 1973, 1, 51-63. [all data]

Tibor and Anna, 1971
Tibor, T.; Anna, B., Gázkromatográfiás retenció és a kémiai szerkezet, I., Magy. Kem. Foly., 1971, 77, 576-587. [all data]

Ramsey, Lee, et al., 1980
Ramsey, J.D.; Lee, T.D.; Osselton, M.D.; Moffat, A.C., Gas-liquid chromatographic retention indices of 296 non-drug substances on SE-30 or OV-1 likely to be encountered in toxicological analyses, J. Chromatogr., 1980, 184, 2, 185-206, https://doi.org/10.1016/S0021-9673(00)85641-1 . [all data]

Peng, Ding, et al., 1988
Peng, C.T.; Ding, S.F.; Hua, R.L.; Yang, Z.C., Prediction of Retention Indexes I. Structure-Retention Index Relationship on Apolar Columns, J. Chromatogr., 1988, 436, 137-172, https://doi.org/10.1016/S0021-9673(00)94575-8 . [all data]

Goeminne, Vandendriessche, et al., 2012
Goeminne, P.C.; Vandendriessche, T.; Van Eldere, J.; Nicolai, B.M.; Hertog, M.L.; Dupont, L.J., Detection of Pseudomonas aeruginosa in sputum headspace through volatile organic compound analysis, Respiratory Res., 2012, 13, 87, 1-9. [all data]

Farkas, Héberger, et al., 2004
Farkas, O.; Héberger, K.; Zenkevich, I.G., Quantitative structure-retention relationships. XIV. Prediction of gas chromatographic retention indices for saturated O-, N-, and S-heterocyclic compounds, Chemom. Intell. Lab. Syst., 2004, 72, 2, 173-184, https://doi.org/10.1016/j.chemolab.2004.01.012 . [all data]

Flanagan, Streete, et al., 1997
Flanagan, R.J.; Streete, P.J.; Ramsey, J.D., Volatile Substance Abuse, UNODC Technical Series, No 5, United Nations, Office on Drugs and Crime, Vienna International Centre, PO Box 500, A-1400 Vienna, Austria, 1997, 56, retrieved from http://www.odccp.org/pdf/technical_series₁997-01-01₁.pdf. [all data]

Strete, Ruprah, et al., 1992
Strete, P.J.; Ruprah, M.; Ramsey, J.D.; Flanagan, R.J., Detection and identification of volatile substances by headspace capillary gas chromatography to aid the diagnosis of acute poisoning, Analyst, 1992, 117, 7, 1111-1127, https://doi.org/10.1039/an9921701111 . [all data]

Waggott and Davies, 1984
Waggott, A.; Davies, I.W., Identification of organic pollutants using linear temperature programmed retention indices (LTPRIs) - Part II, 1984, retrieved from http://dwi.defra.gov.uk/research/completed-research/reports/dwi0383.pdf. [all data]

Ramsey and Flanagan, 1982
Ramsey, J.D.; Flanagan, R.J., Detection and Identification of Volatile Organic Compounds in Blood by Headspace Gas Chromatography as an Aid to the Diagnosis of Solvent Abuse, J. Chromatogr., 1982, 240, 2, 423-444, https://doi.org/10.1016/S0021-9673(00)99622-5 . [all data]

Ardrey and Moffat, 1981
Ardrey, R.E.; Moffat, A.C., Gas-liquid chromatographic retention indices of 1318 substances of toxicological interest on SE-30 or OV-1 stationary phase, J. Chromatogr., 1981, 220, 3, 195-252, https://doi.org/10.1016/S0021-9673(00)81925-1 . [all data]

Rochat, Egger, et al., 2009
Rochat, S.; Egger, J.; Chaintreau, A., Strategy for the identification of key odorants: application to shrimp aroma, J. Chromatogr. A, 2009, 1216, 36, 6424-6432, https://doi.org/10.1016/j.chroma.2009.07.014 . [all data]

Peng, Yang, et al., 1991
Peng, C.T.; Yang, Z.C.; Ding, S.F., Prediction of rentention idexes. II. Structure-retention index relationship on polar columns, J. Chromatogr., 1991, 586, 1, 85-112, https://doi.org/10.1016/0021-9673(91)80028-F . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), UV/Visible spectrum, Gas Chromatography, References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  Pc	Critical pressure
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  Vc	Critical volume
  ΔHtrs	Enthalpy of phase transition
  ΔStrs	Entropy of phase transition
  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
  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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