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C‐aryl glycosyl compounds offer better in vivo stability relative toO‐ andN‐glycoside analogues.C‐aryl glycosides are extensively investigated as drug candidates and applied to chemical biology studies. Previously,C‐aryl glycosides were derived from lactones, glycals, glycosyl stannanes, and halides, via methods displaying various limitations with respect to the scope, functional‐group compatibility, and practicality. Challenges remain in the synthesis ofC‐aryl nucleosides and 2‐deoxysugars from easily accessible carbohydrate precursors. Herein, we report a cross‐coupling method to prepareC‐aryl and heteroaryl glycosides, including nucleosides and 2‐deoxysugars, from glycosyl esters and bromoarenes. Activation of the carbohydrate substrates leverages dihydropyridine (DHP) as an activating group followed by decarboxylation to generate a glycosyl radical via C−O bond homolysis. This strategy represents a new means to activate alcohols as a cross‐coupling partner. The convenient preparation of glycosyl esters and their stability exemplifies the potential of this method in medicinal chemistry.

Applications of TEMPO^.catalysis for the development of redox‐neutral transformations are rare. Reported here is the first TEMPO^.‐catalyzed, redox‐neutral C−H di‐ and trifluoromethoxylation of (hetero)arenes. The reaction exhibits a broad substrate scope, has high functional‐group tolerance, and can be employed for the late‐stage functionalization of complex druglike molecules. Kinetic measurements, isolation and resubjection of catalytic intermediates, UV/Vis studies, and DFT calculations support the proposed oxidative TEMPO^./TEMPO⁺redox catalytic cycle. Mechanistic studies also suggest that Li₂CO₃plays an important role in preventing catalyst deactivation. These findings will provide new insights into the design and development of novel reactions through redox‐neutral TEMPO^.catalysis.