N-Si Heterolysis by Chiral (BOX)Cu(OTf)2 Catalysts for the Synthesis of Indole and Carbazole Glycosides

Org Lett. 2024 Jun 14;26(23):4975-4979. doi: 10.1021/acs.orglett.4c01584. Epub 2024 Jun 3.

Abstract

Chiral Cu(II) bisoxazolines have been shown to catalyze the coupling of acetyl-protected carbohydrates with N-silylated indoles to give the corresponding N-glycosides. Preliminary mechanistic experiments indicated that catalysis occurs through formation of a Cu-indolide complex with concomitant formation of TMS-OTf which together activate the sugar and deliver the indole nucleophile.