Efficient synthesis of 2-benzofuranyl C-glycosides by one-pot cascade reaction of sugar alkynes and substituted 2-iodophenols

2-Benzofuranyl C-glycosides were synthesized in good to excellent yields by one-pot cascade reaction of terminal sugar alkynes and substituted 2-iodophenols. The products have wide structural diversity and potential biological activity. This new synthetic method is general, mild, and efficient. Thirty-seven examples have been given. The structurally diverse terminal sugar alkynes included pyranosides, furanosides, and acyclic sugars with sensitive and bulky protecting groups. The substituted 2-iodophenols contained electron-donating, electron-withdrawing, and electron-neutral substituents. The mechanism for the formation of the products has been proposed.