Influence of a Two-Fold Ligation Pattern on Iron-Mediated Aryl–Heteroaryl Cross-Electrophile Couplings

An aryl-heteroaryl cross-electrophile coupling (XEC) relying on the use of a single, well-defined iron catalyst is disclosed, involving magnesium as an electron source as well as heteroaryl chlorides and aryl iodides or bromides as coupling partners. A 2-fold coordination pattern featuring a π-acceptor, redox-active (N,N) ligand, along with a σ-donating phosphine ensures both the two-electron reduction of the starting iron-(II) precursor to enter the cycle and access to stable organoiron-(II) resting states, inhibiting the reductive decomposition of the catalyst.