Yb(OTf)3-catalyzed C-glycosylation:: highly stereoselective synthesis of C-pseudoglycals

A variety of functionalized C-pseudoglycals (pseudoglycal C-glycosides or C-hex-2-enopyranosides) have been obtained in excellent yields and stereoselectivity from the Yb(OTf)(3)-catalyzed reaction of tri-O-acelyl glucal with silylated nucleophiles such as allyl and propargyl silanes and silyl enol ethers. (C) 2001 Elsevier Science Ltd. All rights reserved.