Collect. Czech. Chem. Commun.
1979, 44, 1949-1964
https://doi.org/10.1135/cccc19791949
The 1H NMR spectra and the conformation of 1,6-anhydro-β-D-hexopyranoses and their triacetates
Miloš Buděšínskýa, Tomáš Trnkab and Miloslav Černýb
a Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague 6
b Department of Organic Chemistry, Charles University, 128 40 Prague 2
Abstract
The 1H NMR spectra of 1,6-anhydro-β-D-hexopyranoses and their triacetates, measured in hexadeuteriodimethyl sulfoxide or deuteriochloroform, confirmed the existence of these compounds in 1C4(D) conformations, with the pyranose ring partly planarized in dependence on the configuration of the substituents in positions C(2), C(3) and C(4). The effects of the substituents on the chemical shifts and the adjusted relationship for the dependence of vicinal coupling constants on the torsion angle are discussed in detail from the point of view of the determination of the configuration and the conformation of 1,6-anhydro-β-D-hexopyranoses and their derivatives. The 1H NMR spectra of triacetates were also measured in the presence of the lanthanide shift reagent, tris(1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octanedione) europium (III) [Eu.(FOD)3].
