C5R5–iron complexes (R = H or Me) of polyaromatic hydrocarbons: stabilization of the monoreduced state and large variation of spin distribution as a function of the ligand structures

Several new polyaromatic iron complexes have been synthesized with C5H5 or C5Me5 ligands and the synthesis of others is much improved using molten components; cyclic voltammetry shows a considerable stabilization of the FeI state by permethylation of the C5H5 ligand, and a wide range of spin distribution on the polyaromatic ligand: biphenyl ∼ triphenylene ⩽ naphthalene < phenanthrene < pyrene < perylene ⩽ corronene, is found for the C5H5 complexes only.