Azetidines are prominent structural scaffolds in bioactive molecules, medicinal chemistry, and ligand design for transition metals. However, state-of-the-art methods cannot be applied to intramolecular hydroamination of allylic amine derivatives despite their underlying potential as one of the most prevalent synthetic precursors to azetidines. Herein, Prof. Hyunwoo Kim group at POSTECH and co-workers report an electrocatalytic method for intramolecular hydroamination of allylic sulfonamides to access azetidines for the first time. The merger of cobalt catalysis and electricity enables regioselective generation of key carbocationic intermediates, which could directly undergo intramolecular C-N bond formation. The mechanistic investigations including electrochemical kinetic analysis suggest that either the catalyst regeneration by nucleophilic cyclization or the second electrochemical oxidation to access carbocationic intermediate is involved in the rate-determining step (RDS) of our electrochemical protocol and highlight the ability of electrochemistry in providing ideal means to mediate catalyst oxidation.

                                                   Electrocatalytic Access to Azetidines via Intramolecular Allylic Hydroamination 

[Reference] Kim H. et al., (2023) “Electrocatalytic Access to Azetidines via Intramolecular Allylic Hydroamination: Scrutinizing Key Oxidation Steps through Electrochemical Kinetic Analysis” Journal of the American Chemical Society

[Main Author] Steve H Park (POSTECH), Ahhyeon Choi (POSTECH), Geunsu Bae (POSTECH), Chang Hyuck Choi (POSTECH), Hyunwoo Kim (POSTECH)

* Contact email : Professor Hyunwoo Kim (khw7373@postech.ac.kr)