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On the stereochemistry of 1,4-diheterocyclanes. IV—carbon-13 NMR spectra and structural properties of 1,4-dioxane-2,3-diols and their methyl-substituted derivatives

✍ Scribed by Pertti Äyräs

Publisher
John Wiley and Sons
Year
1978
Tongue
English
Weight
463 KB
Volume
11
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The 1,4‐dioxane‐2,3‐diols and a number of their methyl‐substituted derivatives were synthesized and their ^13^C NMR spectra measured. The configurational properties were studied on the basis of the spectral data and chemical equilibration. For the parent compound the trans configuration is slightly more stable. The hydroxyl groups are predominantly axial. Introduction of a methyl group at the 2 position causes the cis configuration of the hydroxyl substituents to become more stable. The substituent effects on the chemical shifts were calculated and used to test the conformational homogeneity of the compounds. The results indicate a biased (chair) conformation for all the methyl‐substituted derivatives which were studied. Methyl groups have strongly predominating equatorial orientation in each case studied.

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