Redox-Induced Intramolecular C-C Coupling of Acyclic Bis(2-pyridylmethylene)ethylenediamine on a Ru(acac)(2) Platform

The paper documents redox-triggered C-C coupling of acyclicN,N '-bis(2-pyridylmethylene)ethylenediamine (BPE)to yield 2,3-bis(2-pyridyl)pyrazine (DPP) upon coordination to an electron-rich {Ru(acac)2} (acac = acetylacetonate) unit. This ledto DPP-bridged [{Ru(acac)2}2(DPP)]0/+(2and [2]ClO4) along with the unperturbed BPE-bridged [{Ru(acac)2}2(BPE)] (1). Onthe contrary, electron-poor {Ru(Cl)(H)(CO)(PPh3)3} yielded BPE-bridged [3](ClO4)2as an exclusive product. Synergistic metal(Ru)-ligand (BPE) redox participation toward chemical noninnocence of the Schiffbase ligand and DPP-mediated electroniccommunication in RuIIRuIII-derived [2]ClO4are addressed