35023-57-5

Upstream product

• 554-84-7 meta-nitrophenol 
• 604-68-2 α-D-glucopyranose peracetylate 
• 3947-62-4 2,3,4,5-tetra-O-acetyl-D-glucopyranose 
• 13331-27-6 m-nitrobenzene boronic acid 
• 74808-10-9 2,3,4,6-tetra-O-acetyl-d-glucopyranosyl trichloroacetimidate 

Downstream Products

• 56140-66-0 m-nitrophenyl-α-D-galactopyranoside 

Relevant academic research and scientific papers

Copper-Catalyzed Anomeric O-Arylation of Carbohydrate Derivatives at Room Temperature

Direct and practical anomeric O-arylation of sugar lactols with substituted arylboronic acids has been established. Using copper catalysis at room temperature under an air atmosphere, the protocol proved to be general, and a variety of aryl O-glycosides have been prepared in good to excellent yields. Furthermore, this approach was extended successfully to unprotected carbohydrates, including α-mannose, and it was demonstrated here how the interaction between carbohydrates and boronic acids can be combined with copper catalysis to achieve selective anomeric O-arylation.

Revisit of the phenol O-glycosylation with glycosyl imidates, BF 3·OEt2 is a better catalyst than TMSOTf

With BF3·OEt2 as the catalyst, the glycosylation of phenols with glycosyl trichloroacetimidates (or N-phenyl trifluoroacetimidates) bearing 2-O-participating groups leads to the desired 1,2-trans-O-glycosides in generally excellent yields without formation of the 1,2-cis-anomers. However, with TMSOTf as the catalyst, the outcomes of the corresponding phenol O-glycosylation are highly dependent on the nucleophilicity of the phenols; less nucleophilic is the phenol, higher amounts of the 1,2-cis-O-glycoside together with more side-products are generated. 1,2-Orthoesters have been found to be the major products at a low temperature (a higher temperature. BF 3·OEt2 is an effective catalyst to promote the conversion of 1,2-orthoesters into the corresponding 1,2-trans-O-glycosides. However, the 1,2-orthoesters could be converted into the dioxolenium triflate and glycosyl triflate in the presence of TMSOTf, these intermediates which might be in equilibrium with the glycosyl oxocarbenium related species lead to the final mixture of the α/β-O-glycosides and side-products.