Pd-catalyzed synthesis of hetero 1,2-interlinked C-disaccharides by coupling of iodo glycals with glycals†
Abstract
A facile synthesis of C1–C2 interlinked disaccharides is achieved from readily available iodo-glycals and unsubstituted glycals. Ester-protected donors reacted with ether-protected acceptors under Pd-Ag catalysis to access C-disaccharides bearing C-3 vinyl ether, which upon ring opening by Lewis acid furnished pi-extended conjugated orthogonally protected chiral ketones. Benzyl deprotection and reduction of the double bonds resulted in a fully saturated disaccharide stable toward acid hydrolysis.