Fluoride Migration Catalysis Enables Simple, Stereoselective, and Iterative Glycosylation

Area of Science:

• Carbohydrate Chemistry
• Organic Synthesis
• Catalysis

Background:

• Glycosidic bond formation is crucial for synthesizing oligosaccharides and glycoconjugates.
• Current glycosylation methods face limitations, hindering progress in glycosciences.

Purpose of the Study:

• To develop a novel catalytic strategy for efficient glycosidic bond assembly.
• To overcome limitations in current glycoside synthesis methods.

Main Methods:

• Utilized highly electrophilic boron catalysts, specifically tris(pentafluorophenyl)borane.
• Employed glycosyl fluoride donors and silyl ether acceptors.
• Performed reactions at room temperature with air- and moisture-stable catalysts.

Main Results:

• Achieved efficient glycosylation with low catalyst loadings (0.5 mol %).
• Enabled access to diverse glycosylation patterns, including all C1-C2 stereochemical relationships for glucose, mannose, and rhamnose.
• Demonstrated one-pot, iterative glycosylations to directly form oligosaccharides from monosaccharides.

Conclusions:

• The developed boron-catalyzed method offers a straightforward and rapid approach to complex oligosaccharide synthesis.
• This strategy addresses key challenges in glycosidic bond formation, advancing the field of glycosciences.