Proline

• Formula: C₅H₉NO₂
• Molecular weight: 115.1305
• IUPAC Standard InChI: InChI=1S/C5H9NO2/c7-5(8)4-2-1-3-6-4/h4,6H,1-3H2,(H,7,8)/t4-/m1/s1 Copy

  
• IUPAC Standard InChIKey: ONIBWKKTOPOVIA-SCSAIBSYSA-N Copy
• CAS Registry Number: 147-85-3
• 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.
• Stereoisomers:
  • dl-Proline
• Other names: L-Proline; Proline, L-; (-)-(S)-Proline; L-(-)-Proline; 2-Pyrrolidinecarboxylic acid; 2-Pyrrolidinecarboxylic acid, (S)-
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Data at other public NIST sites:
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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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 solid

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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of sublimation

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 by: John E. Bartmess

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

C₅H₈NO₂^- +  =

By formula: C₅H₈NO₂^- + H⁺ = C₅H₉NO₂

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:
B - John E. Bartmess
MM - Michael M. Meot-Ner (Mautner)
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Proton affinity at 298K

Gas basicity at 298K

Ionization energy determinations

De-protonation reactions

C₅H₈NO₂^- +  =

By formula: C₅H₈NO₂^- + H⁺ = C₅H₉NO₂

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, 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.

Sabbah and Laffitte, 1978
Sabbah, R.; Laffitte, M., Thermodynamique de composes azotes. IV. Etude thermochimique de la sarcosine et de la L-proline, Bull. Soc. Chim. Fr., 1978, 1, 50-52. [all data]

Sabbath and Laffitte, 1978
Sabbath, R.; Laffitte, M., Enthalpy of formation of solid L-proline, J. Chem. Thermodyn., 1978, 10, 101-102. [all data]

Vasilev, Borodin, et al., 1989
Vasilev, V.P.; Borodin, V.A.; Kopnyshev, S.B., Standard enthalpies of formation of L-histidine and L-proline, Russ. J. Phys. Chem. (Engl. Transl.), 1989, 63, 891-892. [all data]

Cole, Hutchens, et al., 1963
Cole, A.G.; Hutchens, J.O.; Stout, J.W., Heat capacities from 11 to 305°K. and entropies of L-phenylalanine, L-proline, L-tryptophane, and L-tyrosine. Some free energies of formation, J. Phys. Chem., 1963, 67, 1852-1855. [all data]

Huffman and Fox, 1940
Huffman, H.M.; Fox, S.W., Thermal data. XIII. The heat capacities and entropies of creatine hydrate, DL-citrulline, DL-ornithine, L-proline and taurine, J. Am. Chem. Soc., 1940, 62, 3464-3465. [all data]

Spink and Wads, 1975
Spink, C.H.; Wads, I., Thermochemistry of solutions of biochemical model compounds. 4. The partial molar heat capacities of some amino acids in aqueous solution, J. Chem. Thermodynam., 1975, 7, 561-572. [all data]

de Kruif, Voogd, et al., 1979
de Kruif, C.G.; Voogd, J.; Offringa, J.C.A., Enthalpies of sublimation and vapour pressures of 14 amino acids and peptides, The Journal of Chemical Thermodynamics, 1979, 11, 7, 651-656, https://doi.org/10.1016/0021-9614(79)90030-2 . [all data]

Sabbah and Laffite, 1978
Sabbah, R.; Laffite, M., Bull. Soc. Chim. Fr., 1978, 1, 50. [all data]

Svec and Clyde, 1965
Svec, H.J.; Clyde, D.D., Vapor pressures of some α-amino acids, J. Chem. Eng. Data, 1965, 10, 151. [all data]

O'Hair, Bowie, et al., 1992
O'Hair, R.J.; Bowie, J.H.; Gronert, S., Gas Phase Acidity of the alpha-Amino Acids, Int. J. Mass Spectrom. Ion Proc., 1992, 117, 23, https://doi.org/10.1016/0168-1176(92)80083-D . [all data]

Jones, Bernier, et al., 2007
Jones, C.M.; Bernier, M.; Carson, E.; Colyer, K.E.; Metz, R.; Pawlow, A.; Wischow, E.D.; Webb, I.; Andriole, E.J.; Poutsma, J.C., Gas-phase Acities of the 20 Protein Amino Acids, Int. J. Mass Spectrom., 2007, 267, 1-3, 54-62, https://doi.org/10.1016/j.ijms.2007.02.018 . [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]

Bouchoux and Salpin, 2003
Bouchoux, G.; Salpin, J.Y., Gas-phase basicity of glycine, alanine, proline, serine, lysine, histidine and some of their peptides by the thermokinetic method, European J. Mass Spectrometry, 2003, 9, 391-402. [all data]

Mezzache, Afonso, et al., 2003
Mezzache, S.; Afonso, C.; Pepe, C.; Karoyan, P.; Fournier, F.; Tabet, J.C., Proton Affinity of Proline and Modified Prolines Using the Kinetic Method: Role of the Conformation Investigated by ab intio Calculations, Rapid Comm. Mass Spectrometry, 2003, 17, 1626. [all data]

Mirza, Prabhakar, et al., 2001
Mirza, S.P.; Prabhakar, S.; Vairamani, M., Estimation of proton affinity of proline and tryptophan under electrospray ionization conditions using the extended kinetic method, Rapid Comm. Mass Spectrometry, 2001, 15, 957. [all data]

Bojesen and Breindahl, 1994
Bojesen, G.; Breindahl, T., On the Proton Affinity od Some Alpha-Amino Acids and the Theory of the Kinetic Method., J. Chem. Soc. Perkin 2, 1994, 1029. [all data]

Cannington and Ham, 1983
Cannington, P.H.; Ham, N.S., He(I) and He(II) photoelectron spectra of glycine and related molecules, J. Electron Spectrosc. Relat. Phenom., 1983, 32, 139. [all data]

Slifkin and Allison, 1967
Slifkin, M.A.; Allison, A.C., Measurement of ionization potentials from contact charge transfer spectra, Nature, 1967, 215, 949. [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, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  Cp,solid	Constant pressure heat capacity of solid
  S°solid,1 bar	Entropy of solid at standard conditions (1 bar)
  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔsubH°	Enthalpy of sublimation at standard conditions

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