Mannopyranosyl fluoride preparation

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... 

Tetra-Q-benzyl-o-D-mannopyranosyl fluoride, used together with bis(cyclopentadienyl)zirconium chloride and silver tetrafluoroborate, affords an effective means of preparing o-linked mannopyranosyl disaccharides, and -linked analogues can be made by way of 2-O-imidazolsulphonates of -D-glucose linked compounds as can 2-amino-2-deoxy- -D-mannopyranosyl compounds. The synthesis of the dermatan sulphate disaccharides (45a) and (45b)... 

---