Nickel-Catalyzed Cyanation of Aryl Triflates Using Acetonitrile as a Cyano Source

Abstract

In classic cyanation reactions, toxic metal cyanide sources or complex organic cyanide sources are often used. Therefore, it is particularly important to develop a green and economical cyano source. Initially, 4-biphenylyl trifluoromethanesulfonate is chosen as the model substrate. Through extensive screening of catalysts, ligands, additives, reductant, temperature and other conditions, the optimal conditions are obtained (Ni(OTf)2, 1, 3-bis (diphenyphosphino)propane, Zn(OTf)2, Zn with a mole fraction of 0.1, 0.1, 0.2, 2, respectively, 0.7 mL CH3CN, N2, 60 h, 100 ℃). Subsequently, the generation and limitations of the substrates are studied under optimal conditions. It is found that substrates bearing electron-donating substituents exhibit an excellent efficiency for the cyanation of aryl trifluoromethanesulfonates. The cyanation of aryl trifluoromethanesulfonates is first realized under the catalysis of nickel with acetonitrile as a green and economical cyano source.

Keywords

• cyanation
• acetonitrile
• nickel catalyst
• imine intermediate