Synthesis of Reversed C-Acyl Glycosides through Ni/Photoredox Dual Catalysis

Abstract

The incorporation of C-glycosides in drug design has become a routine practice for medicinal chemists. These naturally occurring building blocks exhibit attractive pharmaceutical profiles, and have become an important target of synthetic efforts in recent decades. Described herein is a practical, scalable, and versatile route for the synthesis of non-anomeric and unexploited C-acyl glycosides through a Ni/photoredox dual catalytic system. By utilizing an organic photocatalyst, a range of glycosyl-based radicals are generated and efficiently coupled with highly functionalized carboxylic acids at room temperature. Distinctive features of this transformation include its mild conditions, impressive compatibility with a wide array of functional groups, and most significantly, preservation of the anomeric carbon: a handle for further, late-stage derivatization.

Keywords: 1,4-dihydropyridines; acylation; carboxylic acids; glycosides; single-electron transfer.