Ferrier-Type Alkynylation Reaction Mediated by Indium

An efficient Ferrier-type alkynylation reaction between glycals and iodoalkynes using Barbier conditions is described. These conditions require In0, InI, or InII and lead to α-2,3-unsaturated-C-glycosides with good stereoselectivity. When glycosyliodoalkynes are used, trehalose-derived compounds and α-(1→6)-C-disaccharides are obtained.