Electrochemical amidochlorination between low-cost styrenes and amides

Abstract

2-Chloroalkylamines are essential motifs in biologically active molecules and a class of amphoteric molecules which play an important role in the synthesis of drugs and agrochemicals. Amidochlorination of easily accessible alkenes is one of the most desirable transformations for synthesizing important 2-chloroalkylamines. However, their preparation from cheap and readily available amides remains challenging. Here, we report an electrochemical strategy to achieve amidochlorination between low-cost styrenes and amides without additional chlorinated reagents. The reaction proceeds in DCE under mild conditions and tolerates a large scope of styrenes and amides, delivering high yields. Mechanistic studies show that DCE can effectively supply chlorine anions under electrochemical conditions. Chloride anions can be further oxidized to chlorine, which is captured by an alkene to form a chloronium species; then, amide reacts with the chloronium species intermediate to afford the amidochlorination product, which provides a new way for chlorination.