4,5-Dioxo-imidazolinium Cation-Promoted α‑Selective Dehydrative Glycosylation of 2‑Deoxy- and 2,6-Dideoxy Sugars

Herein, we report the great potential
of the 4,5-dioxo-imidazolinium
cation activation strategy for dehydrative glycosylation reactions
employing the readily available and economical geminal dichloroimidazolidinediones
(DCIDs) that promotes the glycosylation between 2-deoxy- and 2,6-dideoxy-sugar
hemiacetals with various acceptors in good yields and high α-selectivity.
This research not only provides a mild and efficient alternative approach
for stereoselective dehydrative glycosylation but also extends the
dichloroimidazolidinedione as a novel promoter in the field of glycoscience.