The Stereochemistry of 1,2,3‐Triols Revealed by 1H NMR Spectroscopy: Principles and Applications |
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| Authors: | Félix Freire Dr. Enrique Lallana Emilio Quiñoá Prof. Dr. Ricardo Riguera Prof. Dr. |
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| Affiliation: | Department of Chemistry, University of Santiago de Compostela, Avd. Ciencias s/n. E‐15782 (Spain), Fax: (+34)?981‐591‐091 |
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| Abstract: | The conformational compositions of the tris(α‐methoxy‐α‐phenylacetic acid) ester derivatives of 1,2,3‐prim,sec,sec‐triols are presented. These conformations have been determined by theoretical and experimental data (i.e., energy‐ and chemical‐shift calculations, circular dichroism (CD) experiments, coupling‐constant analysis, enantioselective deuteration experiments, and low‐temperature NMR spectroscopic studies). A detailed analysis of the anisotropic effects due to the most significant conformers in the 1H NMR spectra supported the correlation between the 1H NMR spectra (ΔδRS value of H(3′) and |Δ(ΔδRS)| parameters) and the absolute configuration of the substrate. The study also allows the identification of the pro‐R and pro‐S methylene protons from their vicinal coupling constants and relative chemical shifts. |
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| Keywords: | alcohols configuration determination conformation analysis methoxyphenylacetic acid NMR spectroscopy |
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