Synthesis and Electrochemical Properties of Mixed-Metal Triangular Complexes Based on Ferrocene-Based Ligands and Dinuclear Arene Ruthenium Building Blocks

Ferrocene-based multidentate ligands have been widely used as metalloligands in crystal engineering because they self-assemble into mixed-metal complexes with various transition-metal salts. In the present study, the ferrocene-based ligand 1,2-di(4-pyridylthio)ferrocene (L-Fc) was complexed with dinuclear arene ruthenium building blocks [(p-cymene)(2)Ru-2(mu-L)](OTf)(2) to form the following trinuclear complexes with triangular structures: [(p-cymene)(2)Ru-2(mu-L)(mu-L-Fc)](OTf)(2) [L=5,8-dioxido-1,4-naphtoquinonato (1 a), 2,3-dichloro-5,8-dioxido-1,4-naphtoquinonato (1 b), 2,5-dioxido-1,4-benzoquinonato (2 a), 2,5-dichloro-3,6-dioxido-1,4-benzoquinonato (2 b), and oxalato (3): OTf=trifluoromethanesulfonate]. A similar complexation of the ferrocene-based ligand with [(p-cymene)(2)Ru2Cl4] afforded a V-shaped trinuclear complex [(p-cymene)(2)Ru2Cl4(mu-L-Fc)] (4). This study reveals the crystal structure and electronic states of 1-4. The absorption wavelengths and redox potentials of the trinuclear complexes depended on the type of L.

Automated summary

This study focuses on the crystal structures, absorption wavelengths, and redox potentials of trinuclear complexes formed by ferrocene-based multidentate ligands and various transition-metal salts.