Collect. Czech. Chem. Commun. 2006, 71, 1497-1515

Epoxide Migration and Pseudo-Epoxide Migration of 1,6:2,3- and 1,6:3,4-Dianhydro-β-D-hexopyranoses. Synthesis of Some Deoxy Halo Derivatives of 1,6-Anhydro-β-D-hexopyranoses

Martina Džoganováa,b, Miloslav Černýb, Miloš Buděšínskýa,*, Martin Dračínskýa and Tomáš Trnkab

a Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
b Department of Organic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 128 40 Prague 2, Czech Republic


Epoxide or pseudo-epoxide migration of 1,6:2,3-dianhydro- and 1,6:3,4-dianhydro-β-D-hexopyranoses was effected by treatment with aqueous sodium hydroxide or sodium iodide in acetone to give equilibrium mixtures. Various iodo derivatives of 1,6-anhydro-β-D-hexopyranoses were prepared as potential intermediates for pseudo-epoxide migration. NMR was used for following the reaction mechanism of epoxide and pseudo-epoxide migrations and analysis of reaction mixtures. Experimental data were compared with DFT calculations. Chair-boat equilibration of 1,6-anhydro-3-deoxy-3-halo-β-D-glucopyranoses was discussed.

Keywords: Carbohydrates; Anhydro sugars; Epoxides; Epoxide migration; Pseudo-epoxide migration; NMR spectroscopy; DFT calculations; Conformation analysis.

References: 30 live references.