Preparation of C-Perfluoroalkyl Sugars

The stereoselectivity of all these nucleophilic perfluoroalkylations are generally better than those observed with non fluorinated organometallic species, especially for Grignard reagents. 

Synthesis and application of these compounds depend a lot on the position of the Rf chain. Three cases can be considered  

Compounds having O—CF3 (or O—Rf) and S—CF3 (or S—Rf). They are relatively stable derivatives with interesting amphiphilic properties. Moreover, in some cases they are glycosidase inhibitors. 

Fluoroalcohol ethers, such as —O—CH2—Rf, or ketals of fluoroalkyl ketones. Their synthesis has been described only recently. 

Ethers and ketals in which the Rf chain is separated from the oxygen atom by two or three carbons. In spite of the screen effect due to the di- or trimethylene spacer, fluorine atoms still exert a notable effect. As in the previous case, their synthesis generally requires non conventional methods. 

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