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)-
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Phase change data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Mass spectrum (electron ionization)
• Data at other public NIST sites:
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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Phase change data

Go To: Top, Gas phase ion energetics data, 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
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of sublimation

Gas phase ion energetics data

Go To: Top, Phase change 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

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

References

Go To: Top, Phase change 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.

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]

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]

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]

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]

Notes

Go To: Top, Phase change data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  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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