Electron and proton reservoir complexes: Thermodynamic basis for C-H activation and applications in redox and dendrimer chemistry

This Account focuses on fundamental aspects and applications of the concept of "electron and proton reservoirs". Permethylated electron reservoir iron sandwich complexes, which were known to be excellent reducing agents in th eir neutral 19e Fe-1 form, have recently been shown to be stable strong oxi dants in their dicationic 17e Fe-III form. Thermodynamic, mechanistic, and synthetic aspects of the redox chemistry of these and related organoiron co mplexes are summarized. Proton reservoir properties of these complexes are due to enhanced acidity in their cationic form and result in an original ty pe of activation: perfunctionalization leading to dendritic cores and usefu l metallodendrimers of Variable topology.