SciELO - Scientific Electronic Library Online

vol.58 issue2The Effect of NaOH and KOH on the Characterization of Mesoporous AlOOH Nanostructures in the Hydrothermal Route author indexsubject indexsearch form
Home Pagealphabetic serial listing  

Services on Demand




Related links

  • Have no similar articlesSimilars in SciELO


Journal of the Mexican Chemical Society

Print version ISSN 1870-249X


MORALES-NAVA, Rosmarbel; RAMIREZ-SOLIS, Alejandro  and  FERNANDEZ-ZERTUCHE, Mario. NMR and Theoretical Studies on the Conformational Preferences of Some Non-metal Coordinated N-Enoyl Systems Attached to Common Chiral Auxilaries. J. Mex. Chem. Soc [online]. 2014, vol.58, n.2, pp.89-94. ISSN 1870-249X.

We report a systematic study of a series of N-enoyl systems attached to common oxazolidin-2-ones, oxazolidine-2-thiones and thiazolidine-2-thiones chiral auxiliaries in order to determine the most stable conformation of these compounds. 1H NMR studies show an anti-s-cis structure as the most stable conformation for these series of compounds. Density Functional Theory geometry optimizations and vibrational analysis using the B3LYP exchange-correlation functional with the standard 6-31G** basis sets were done, including solvent effects (chloroform and toluene). Gibbs free energy differences show that the anti-s-cis structures are the most stable conformers lying, on average, ca. 6 kcal/mol lower in energy than the syn-s-cis conformers, widely used to explain the structure and reactivity of N-enoyl systems.

Keywords : Enoyl systems; conformational preferences; chiral auxiliaries; NMR shifts.

        · abstract in Spanish     · text in English     · English ( pdf )


Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License