2001 carbohydrates

carbohydratesU 0500

50 - 192Efficient Stereocontrolled Synthesis of C-Glycosides Using GlycosylDonors Substituted by Propane 1,3-Diyl Phosphate as the LeavingGroup. — The treatment of O-acetyl or O-benzyl protected glycosyldonors, bearing propane-1,3-diyl phosphate as an anomeric leaving group, withTmsCN or allyltrimethylsilane in the presence of stoichiometric or catalyticamounts of TmsOTf as an anomeric activator affords the corresponding α- andβ-glycosyl cyanides and glycosylpropenes with varying stereoselectivity. It isdemonstrated, that 1,2-O-1-cyanoethylidene glycoses such as (IV)/(V) can beisolated as intermediates of the reaction of glycosyl donors (I) or (VI) withTmsCN. — (SINGH, GURDIAL; VANKAYALAPATI, HARIPRASAD; Tetra-hedron: Asymmetry 12 (2001) 12, 1727-1735; Chem. Dep., Univ. Sunderland,Sunderland SR1 3SD, UK; EN)

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