L-Isoleucine

• Formula: C₆H₁₃NO₂
• Molecular weight: 131.1729
• IUPAC Standard InChI: InChI=1S/C6H13NO2/c1-3-4(2)5(7)6(8)9/h4-5H,3,7H2,1-2H3,(H,8,9)/t4-,5+/m0/s1 Copy

  
• IUPAC Standard InChIKey: AGPKZVBTJJNPAG-CRCLSJGQSA-N Copy
• CAS Registry Number: 73-32-5
• Chemical structure:
  This structure is also available as a 2d Mol file
• Stereoisomers:
  • allo-L-isoleucine
  • DL-Isoleucine
• Other names: Isoleucine, L-; α-Amino-β-methylvaleric acid, (2S,3S)-; Acetic acid, amino(1-methylpropyl)-, (R*,R*)-; L-(+)-Isoleucine; L-Norvaline, 3-methyl-, erythro-; Norvaline, 3-methyl-, erythro-; Pentanoic acid, 2-amino-3-methyl-, (2S,3S)-; Pentanoic acid, 2-amino-3-methyl-, [S-(R*,R*)]-; Valeric acid, 2-amino-3-methyl-; 2-Amino-3-methylpentanoic acid, (S-(R*,R*))-; 2-Amino-3-methylvaleric acid; sec-C4H9CH(NH2)COOH; Acetic acid, amino-sec-butyl-; [S-(R*,R*)]-2-Amino-3-methylpentanoic acid; (2S,3S)-2-Amino-3-methylpentanoic acid; (2S,3S)-α-Amino-β-methyl-n-valeric acid; (S)-Isoleucine; (S,S)-Isoleucine; 2S,3S-Isoleucine; L-Ile; Isoleucine; NSC 46708; erythro-L-Isoleucine
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
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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)
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Proton affinity at 298K

Ionization energy determinations

De-protonation reactions

C₆H₁₂NO₂^- +  =

By formula: C₆H₁₂NO₂^- + H⁺ = C₆H₁₃NO₂

References

Go To: Top, 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.

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]

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]

Klasinc, 1976
Klasinc, L., Application of photoelectron spectroscopy to biologically active molecules and their constituent parts, J. Electron Spectrosc. Relat. Phenom., 1976, 8, 161. [all data]

Junk and Svec, 1963
Junk, G.; Svec, H., The mass spectra of the α-amino acids, J. Am. Chem. Soc., 1963, 85, 839. [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]

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]

Notes

Go To: Top, 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

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