Palladium-Catalyzed ortho -C-H Glycosylation/ ipso -Alkenylation of Aryl Iodides.

This report describes the first example of palladium-catalyzed ortho -C-H glycosylation/ ipso -alkenylation of aryl iodides, and the easily accessible glycosyl chlorides are used as a glycosylation reagent. The reaction is compatible with the functional groups of the substrates, and a series of C-aryl glycosides have been synthesized in good to excellent yield and with excellent diastereoselectivity. It is found that a cheap 5-norbornene-2-carbonitrile as a transient mediator can effectively promote this reaction. In addition, ipso -arylation and cyanation were also realized by the strategy.