Fig. 4: Mechanistic elucidation of the nickel-electrocatalysed C–H activation process.

a, Determination of the reversibility of C–H activation through H/D exchange study. b, Stoichiometric reaction using complex NiII-DMAP with alkene 2 showing no product formation. c, Stoichiometric reaction using complex NiII-DMAP with alkene 2 with [Cp2Fe]PF6 as redox reagent leading to product 3. d, Synthesis of the cyclometallated complex NiIII-L7 under electrochemical conditions. The structure of NiIII-L7 is derived from the X-ray structure obtained for complex NiIII-L11 (CCDC 2278180).