Resumen

JUARISTI, Eusebio  y  MUNOZ-MUNIZ, Omar. Enthalpic and Entropic Contributions to the Conformational Free Energy Differences in Monosubstituted Cyclohexanes. Rev. Soc. Quím. Méx [online]. 2001, vol.45, n.4, pp.218-224. ISSN 0583-7693.

Variable-temperature ¹H and ¹³C NMR spectroscopy of substituted cyclohexanes permitted the evaluation of the thermodynamic parameters for the axial ⇌ equatorial conformational equilibria when the substituent is methyl, ethyl, isopropyl, tert-butyl, benzyl, and the sulfur-containing methylthio, methylsulfinyl, and methylsulfonyl. Interpretation of the results confirms the premise that a proper understanding of conformational preferences requires the knowledge of the enthalpic and entropic contributions to the conformational free energy differences. A comment on the determination of thermodynamic parameters by means of theoretical methods is also included.

Palabras llave : Conformational analysis; A-values, NMR spectroscopy; Variable-temperature NMR.

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