Stereoselective synthesis of 2-deoxy-beta-glycosides using anomeric O-alkylation/arylation.
نویسندگان
چکیده
Anomeric O-alkylation/arylation is applied to the synthesis of 2-deoxy-beta-glycosides. Treatment of lactols with NaH in dioxane followed by the addition of electrophiles leads to the formation of 2-deoxy-beta-glycosides in high yield and high selectivity. The high beta-selectivity observed here demonstrates a powerful stereoelectronic effect for the stereoselective formation of acetals under kinetic control.
منابع مشابه
Stereoselective synthesis of 2-S-phenyl-2-deoxy-beta-glycosides using phenyl 2,3-O-thionocarbonyl-1-thioglycoside donors via 1,2-Migration and concurrent glycosidation.
[figure: see text] 1,2-Migration and concurrent glycosidation of phenyl 2,3-O-thionocarbonyl-1-thlo-alpha-L-rhamnopyranosides under the action of methyl trifluoromethanesulfonate (MeOTf) afforded in high yields the 3-O-(methylthio)carbonyl-2-S-phenyl-2,6-dideoxy-beta-L-glucopyranosides, ready precursors to the corresponding 2-deoxy-beta-glycosides.
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ورودعنوان ژورنال:
- Organic letters
دوره 11 1 شماره
صفحات -
تاریخ انتشار 2009