<i>O</i>‑Glycosylation Enabled by <i>N-</i>(Glycosyloxy)acetamides

A novel glycosylation protocol has been established by using <i>N</i>-(glycosyloxy)­acetamides as glycosyl donors. The <i>N</i>-oxyacetamide leaving group in donors could be rapidly activated in the presence of Cu­(OTf)₂ or SnCl₄ under microwave irradiation. This glycosylation process afforded the coupled products in high yields, and the reaction enjoyed a broad substrate scope, even for disarmed donors and hindered acceptors. The easy availability of the donors, the high stability of <i>N-</i>(glycosyloxy)­acetamides, and the small leaving group make this method very practical.