title: Activation of glycosyl trichloroacetimidates with perchloric acid on silica (HClO(4)-SiO(2)) provides enhanced alpha-selectivity.
abstract: Obtaining high stereoselectivity in glycosylation reactions is often challenging in the absence of neighboring group participation. In this study, we demonstrate that activation of glycosyl trichloroacetimidate donors with immobilized perchloric acid on silica (HClO(4)-SiO(2)) provides higher alpha-selectivity than trimethylsilyl triflate (TMSOTf) for reactions that do not involve neighboring group participation.
authors.affiliation: Chemical Biology Laboratory, National Cancer Institute at Frederick, National Institutes of Health, 376 Boyles St., Frederick, MD 21702, USA.
authors.forename: Olaf R
authors.initials: OR
authors.lastname: Ludek
authors.forename: Wenlu
authors.initials: W
authors.lastname: Gu
authors.forename: Jeffrey C
authors.initials: JC
authors.lastname: Gildersleeve
mesh_terms: D000081:Acetamides; D002384:Catalysis; D062845:Chloroacetates; D006027:Glycosides / Q000138:chemical synthesis; D006031:Glycosylation; D010472:Perchlorates / Q000737:chemistry*; D012822:Silicon Dioxide; D013237:Stereoisomerism; D014238:Trichloroacetic Acid / Q000737:chemistry
chemical_list: D000081:Acetamides; D062845:Chloroacetates; D006027:Glycosides; D010472:Perchlorates; D014238:Trichloroacetic Acid; D012822:Silicon Dioxide; C009528:trichloroacetamide