A Cu(OTf)₂-Catalyzed Glycosylation with Glycosyl ortho-N-Phthalimidoylpropynyl Benzoates as Donors

Abstract

A Cu(OTf)2-catalyzed glycosylation protocol using glycosyl ortho-N-phthalimidoylpropynyl benzoates (NPPBs) as donors was disclosed, which features an inexpensive copper catalyst, operationally convenient conditions, high to excellent yields, and a broad substrate scope. Mechanistic studies indicated an isochromen-4-yl copper(II) intermediate arising from the departure of the leaving group.

Catalytic Orthogonal Glycosylation Enabled by Enynal‐Derived Copper Carbenes

“…Among all catalytic methods, a widely studied process employs the benchtop stable alkyne-based donors activated mainly by gold (I/III) and with limited reports of copper catalysts. [24][25][26] While numerous novel glycosylation techniques have emerged, the process still necessitates laborious fine-tuning and trial-and-error approaches for synthesizing diverse glycans. Additionally, these catalytic approaches have several limitations, such as using precious metals (gold/ rhodium), potentially explosive or unsafe diazo compounds, and the need for orthogonality with other donors.…”

Stereoselective Synthesis of β-glycosyl Esters via 1-Hydroxybenzotriazole Mediated Acylation of Glycosyl Hemiacetals

“…β-1- O -acyl glucuronides represent the major metabolites of carboxylic-acid-containing drugs in mammals, which significantly impact their pharmacological and toxicological properties . In addition, glycosyl esters, especially those bearing an activation handle, are prominent glycosyl donors due to their operational stability and synthetic convenience . In particular, glycosyl ortho -alkynylbenzoates and ynenoates were found capable of enacting a S N 2-like glycosylation reaction under the promotion of gold­(I) and silver­(I) catalysts, respectively, leading to coupled glycosides in a stereospecific manner .…”