Stereoselective Synthesis of <i>C</i>‐Vinyl Glycosides via Palladium‐Catalyzed C−H Glycosylation of Alkenes
Qikai Sun, Huixing Zhang, Quanquan Wang, Tianjiao Qiao, Gang He, Gong Chen
Abstract
C-vinyl glycosides are an important class of carbohydrates and pose a unique synthetic challenge. A new strategy has been developed for stereoselective synthesis of C-vinyl glycosides via Pd-catalyzed directed C-H glycosylation of alkenes with glycosyl chloride donors using an easily removable bidentate auxiliary. Both the γ C-H bond of allylamines and the δ C-H bond of homoallyl amine substrates can be glycosylated in high efficiency and with excellent regio- and stereoselectivity. The resulting C-vinyl glycosides can be further converted to a variety of C-alkyl glycosides with high stereospecificity. These reactions offer a broadly applicable method to streamline the synthesis of complex C-vinyl glycosides from easily accessible starting materials.