One-pot chemo-, regio-, and stereoselective double-differential glycosidation mediated by lanthanide triflates
K N Jayaprakash1, Bert Fraser-Reid
1Natural Products and Glycotechnology Research Institute, Inc., 4118 Swarthmore Road, Durham, North Carolina 27707, USA.
Abstract:
Nuanced activation of n-pentenyl, thioglycoside, and trichloroacetimidate donors by lanthanide salts coupled with donor/acceptor matching can simplify oligosaccharide assembly. Thus, a one-pot, double-differential glycosidation process can be designed, in which an n-pentenyl acceptor-diol is chemo- and regioselectively glycosidated by using an n-pentenyl ortho ester under the agency of Yb(OTf)(3)/NIS followed by in situ addition of a 2-O-acylated trichloroacetimidate or ethyl thioglycoside to effect stereoselective glycosidation at the remaining OH.
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