Ni(I) and Ni(II) Ring‐Expanded N‐Heterocyclic Carbene Complexes: C—H Activation, Indole Elimination and Catalytic Hydrodehalogenation.

A nickel N-heterocyclic carbene complex is synthesized via an indole elimination process and successfully applied for the catalytic hydrodechlorination of 1-chloro-4-fluorobenzene (Ia) and hydrodebromination of 1-bromo-4-fluorobenzene (Ia) under mild reaction conditions.