| Abstract
| - A series of anomerically pure 1-O-formyl glycosides 1 was prepared and converted into the corresponding1-O-vinyl glycosides 2 by Tebbe olefination. The unsubstituted vinyl glycosides were obtained asanomerically pure compounds in good yields, and the method of preparation was compatible with thepresence of a variety of functional groups. Remarkably, the anomeric formate group was regioselectivelyconverted into the corresponding olefin in the presence of acetate and benzoate protecting groups. Withthe perspective to use the 1-O-vinyl glycosides as monomers for the preparation of glycosylated poly(vinyl alcohol) derivatives with controlled tacticity, their scope as chiral auxiliaries for a stereodifferentiation in addition reactions to the olefin function was investigated by using the [2+2] cycloadditionto dichloroketene as a model reaction. In particular, vinyl 2,3,4,6-tetra-O-benzoyl-α-d-mannopyranoside(2i) exhibited excellent diastereoselectivity. Finally, the 1-O-vinyl glycosides were successfully subjectedto radical homopolymerization in bulk or used as electron-rich comonomers in radical copolymerizationswith maleic anhydride, yielding alternating, glycosylated poly(vinyl alcohol-alt-maleic anhydride).
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