An α-selective, visible light photocatalytic glycosylation of alcohols with selenoglycosides
Mark Spell1, Xiaoping Wang, Amir E Wahba
1Department of Chemistry, Louisiana State University, 232 Choppin Hall, Baton Rouge, LA 70803, United States.
Abstract:
Exceptionally mild procedures for the visible light photocatalytic activation of selenoglycoside donors in the presence of alcohol acceptors have been developed. This process is demonstrated with both 1-phenylselenyl-2,3,4,6-tetra-O-benzyl glucoside (1) and 1-phenylselenyl-2,3,4,6-tetra-O-benzyl galactoside (2). Catalysis is effected with both metal (Ru(bpy)3) and organocatalysts (diphenyldiselenide). Reactions afford, in all cases, primarily the α-anomers with selectivities that vary with solvent. This represents the first example of a visible light-promoted O-glycosylation.
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