A Macrocyclic Chalcogen Bonding Catalysis System

Abstract

Chalcogen bonding has emeged as a new catalysis strategy capable of solving reactivity and selectivity problems in a diverse array of chemical reactions. Yet, a macrocyclic chalcogen bonding catalysis system remains undeveloped in this field. Here, we report the first example on the development of macrocyclic chalcogen bonding catalysts and the proof-of-concept studies on their catalysis capability. The tellurium centers in these macrocyclic chalcogen bonding catalysts can form competitive host-guest interactions between catalyst and glycosyl acceptors and donors, enabling the development of a dynamic glycosylation approach. In the presence of the same macrocyclic catalyst and the same reactants, the glycosylation process could be controlled to shift between S_N1 and S_N2 reaction pathways through the formation of different host-guest complexes. This dynamic glycosylation mechanism can lead to high stereoselectivity through simply increasing the concentration of glycosyl acceptors.