Mannopyranosyl fluoride

Ci2HieBrF07 3,4,6-Tri-0-acetyl-2-bromo-2-deoxy-a-D-mannopyranosyl fluoride DMANPR10 31 367... 

Silver tetrafluoroborate in ether or toluene has also been used for the synthesis of glycosyl fluorides. Peracetylated 2-chloro-2-deoxy-D-gluco- and -mannopyranosyl fluorides have been prepared by treatment of the corresponding chlorides with the aforementioned reagent.50,51 Products of kinetic control were obtained when diethyl ether was used as the solvent, whereas products of thermodynamic control were obtained when toluene was used instead. Peracetylated... 

On treatment of tri-O-acetyl-D-glucal with chlorine and silver fluoride,198 all four possible isomers were formed tri-0-acetyl-2-chloro-2-deoxy-a-D-mannopyranosyl fluoride (16%), tri-0-acetyl-2-chloro-2-deoxy-/3-D-mannopyranosyl fluoride (16%), tri-0-acetyl-2-chloro-2-deoxy-a-D-glucopyranosyl fluoride (6%), and tri-O-acetyl-2-chloro-2-deoxy-/3-D-glucopyranosyl fluoride (62%). These product ratios differ significantly from those of the corresponding bromofluorination and iodofluorination reactions of tri-O -ace tyl-D-glucal,43,53 and this behavior has been discussed198 in terms of the differences observed between the addition of bromine (or iodine) and chlorine to tri-O-acetyl-D-glu-cal, and the nature of the chlorination reaction itself. 

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