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The NMR spectra and conformations of dihydropyran derivatives—II: The conformational energies of carbomethoxy, hydroxymethyl and acetoxymethyl groups at c-6 of the 5,6-dihydro-α-pyran ring

✍ Scribed by O. Achmatowicz Jr; M. Chmielewski; J. Jurczak; L. Kozerski; A. Zamojski

Publisher
John Wiley and Sons
Year
1972
Tongue
English
Weight
407 KB
Volume
4
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The sum of coupling constants of proton H‐6 for conformations H1 and 1H of the 6‐substituted 5,6‐dihydro‐α‐pyran derivatives have been determined with the aid of appropriate, conformationally biased compounds. With the use of these values and the PMR spectra of the title compounds, thermodynamic values of their conformational equilibria and the conformational preferences of the carbomethoxy, hydroxymethyl and acetoxymethyl groups, have been evaluated.

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✍ Marek Chmielewski; Janusz Jurczak; Aleksander Zamojski; Halina Adamowicz 📂 Article 📅 1982 🏛 John Wiley and Sons 🌐 English ⚖ 474 KB

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