Cooperative Catalysis with Aldehydes and Copper: Development and Application in Aerobic Oxidative CH Amination at Room Temperature

Abstract

AbstractA conceptually new cooperative catalytic system via a synergistic combination of aldehyde and copper catalysis has been established based on systemic mechanistic studies. This new cooperative catalysis has been successfully applied in the direct aerobic oxidative CH amination of azoles at room temperature, which was previously realized under harsh conditions. Mechanistic studies including isotopic labeling experiments and kinetic isotope effect (KIE) experiments support a reaction pathway that involves formation of an aminal, hydrolysis of the aminal to generate the copper‐amide species, subsequent CH amination and re‐oxidation of copper(I) to copper(II) by oxygen. It not only provides an efficient method to realize the oxidative CH amination of benzoxazoles with free amines at room temperature, but also paves the way for establishing new CN bond formation reactions by using this efficient cooperative catalysis.