Fluorine-Directed β-Galactosylation: Chemical Glycosylation Development by Molecular Editing

Validation of the 2‐fluoro substituent as an inert steering group to control chemical glycosylation is presented. A molecular editing study has revealed that the exceptional levels of diastereocontrol in glycosylation processes by using 2‐fluoro‐3,4,6‐tri‐O‐benzyl glucopyranosyl trichloroacetimidate (TCA) scaffolds are a consequence of the 2R,3S,4S stereotriad. This study has also revealed that epimerization at C4, results in a substantial enhancement in β‐selectivity (up to β/α 300:1). Fine‐tuned with fluorine! Validation of the 2‐fluoro substituent as an inert steering group to control chemical glycosylation is presented. A molecular editing study revealed that the exceptional levels of diastereocontrol in glycosylation processes with 2‐F‐3,4,6‐tri‐O‐benzyl glucopyranosyl trichloroacetimidate scaffolds are a consequence of the 2R,3S,4S stereotriad.