A Review on Catalyzed Dimerization of Acrylonitrile

Acrylonitrile (AN) is a cheap and accessible industrial material.Linear dimerization of acrylonitrile affords the skeleton of adiponitrile, which leads to hexamethylene diamine through further hydrogenation.Hexamethylene diamine is an important industrial intermediate with comprehensive applications and wide market requirement and is mainly applied in the synthesis of nylon 66.Therefore, linear dimerization of acrylonitrile is a very important organic reaction.Compared with the electrolytic process which has already been applied in industrial production, the catalyzed dimerization needs low energy consumption and low equipment requirements.Besides, the catalyzed dimerization of acrylonitrile may also afford the branched dimer 2-methyleneglutaronitrile, which is the important intermediate in the synthesis of bromothalonil.Although the market requirement of bromothalonil is not as huge as nylon 66, it is also one of the important chemical industrial products.However, currently, there was no systematic review on AN dimerization.Therefore, this review aims to reorganize and systematically describe the advances of catalyzed dimerization of acrylonitrile for reference of the related technicians in China, including the Ru-catalyzed dimerization, other metal-catalyzed dimerization and phosphorus-catalyzed dimerization.