Phenoxyimine Ligand Molecular Structure Influence on Reversible Magnesium Electrode Reaction in a Magnesium Chloride Complex

Non-aqueous electrolytes containing magnesium chloride complex in which magnesium is coordinated by synthesized phenoxyimine ligand have unique properties for magnesium deposition and dissolution. Those properties have been compared using ligands with different terminal groups. For electrochemical and Raman spectroscopic studies, mixed electrolytes were prepared by dissolving a phenoxyimine–magnesium-chloride complex and magnesium [bis(trifluoromethane sulfonyl)imide] in triglyme solvent. An electrolyte containing phenoxyimine with an n-butyl terminal group shows higher Coulombic efficiency of magnesium deposition than the electrolyte prepared with dimethylamine-terminated phenoxyimine, probably because of preferred formation of active triglyme–magnesium-chloride coordinated cations. By contrast, adding aluminum chloride to the electrolyte with n-butyl-terminated phenoxyimine adversely affected reversible magnesium deposition, probably because trapping of chloride occurred preferentially

Dinuclear Nickel(I) and Palladium(I) Complexes for Highly Active Transformations of Organic Compounds

In typical catalytic organic transformations, transition metals in catalytically active complexes are present in their most stable valence states, such as palladium(0) and (II). However, some dimeric monovalent metal complexes can be stabilized by auxiliary ligands to form diamagnetic compounds with metal–metal bonding interactions. These diamagnetic compounds can act as catalysts while retaining their dimeric forms, split homolytically or heterolytically into monomeric forms, which usually have high activity, or in contrast, become completely deactivated as catalysts. Recently, many studies using group 10 metal complexes containing nickel and palladium have demonstrated that under specific conditions, the active forms of these catalyst precursors are not mononuclear zerovalent complexes, but instead dinuclear monovalent metal complexes. In this mini-review, we have surveyed the preparation, reactivity, and the catalytic processes of dinuclear nickel(I) and palladium(I) complexes, focusing on mechanistic insights into the precatalyst activation systems and the structure and behavior of nickel and palladium intermediates