Glycosyl N-phenyl pentafluorobenzimidates as a new generation of imidate donors for catalytic glycosylation

Glycosyl imidates are among the pioneering donors for catalytic glycosylation. We report a new generation of imidates featuring the presence of a pentafluorophenyl group, introduced via substitution on imidoyl fluoride which is easily prepared, stable and user-friendly. The resulting donors exhibit exceptional shelf stability while can be readily activated to achieve high-yielding glycosylation, encompassing comprehensively aldosyl, ketosyl and ulosonyl donors, and both O- and N-glycosylation acceptors. Notably, the reactivity gradient across different generations of imidates, coupled with the accessible imidate acceptor from selective reaction of imidoyl fluoride at the anomeric hydroxyl group, enables a fully catalytic one-pot synthesis of oligosaccharides.