522592-34-3Relevant academic research and scientific papers
1→2 Migration and concurrent glycosidation of phenyl 1-thio-α-mannopyranosides via 2,3-O-cyclic dioxonium intermediates
Yang, Zunyi,Cao, Hongzhi,Hu, Jie,Shan, Renli,Yu, Biao
, p. 249 - 254 (2003)
Treatment of phenyl 2,3-O-cyclic ketene acetal- and 2,3-O-thionocarbonyl-1-thio-mannopyranosides with TMSOTf and MeOTf, respectively, gave the corresponding 2,3-O-cyclic dioxonium intermediates, which proceeded via 1→2 migration and concurrent glycosidation in the presence of alcohols to provide the corresponding 2-S-phenyl glycosides stereoselectively. While the former donors were too labile, the latter donors have proved superior for the present purpose. The X-ray crystallographic structures of phenyl 4-O-methyl-2,3-O-thiocarbonyl-1-thio-α-L-rhamnopyranoside (1), a typical donor for the present reaction, and its anomeric azide analogue (6), which could not undergo the present reaction under similar conditions, are provided.
