Redox-Active Ligands and Organic Radical Chemistry

Knowledge about bonding in diiminepyridine (L) halide, alkyl, and dinitrogen complexes of the metals iron, cobalt, and nickel is summarized, and two new examples are added to the set: (LNi)-Ni-1(Me) and (LNi)-Ni-1(N-2). Reactivity of these chemistry. New C-C couplings with (LCoAr)-Co-2 complexes are types of complexes is discussed in terms of organic radical described and proposed to involve halide abstraction and radical coupling. Calculations support the high tendency of the diiminepyridine ligand to accept an electron coming from a metal carbon bond and so facilitate loss of a radical.