Abstract
Homobimetallic dicobalt complexes featuring metal centers in different coordination environments have been synthesized, and their multielectron redox chemistry has been investigated. Treatment of CoX2 with MesNKPiPr2 leads to self-assembly of [(THF)Co(MesNPiPr2)2(μ-X)CoX] [X = Cl (1), I (2)], with one Co center bound to two amide donors and the other bound to two phosphine donors. Upon two-electron reduction, a ligand rearrangement occurs to generate the symmetric species (PMe3)Co(MesNPiPr2)2Co(PMe3) (3), where each Co has an identical mixed P/N donor set. One-electron oxidation of 3 to generate a mixed valence species promotes a ligand reararrangement back to an asymmetric configuration in [(THF)Co(MesNPiPr2)2Co(PMe3)][PF6] (4). Complexes 1–4 have been structurally characterized, and their metal–metal interactions are discussed in the context of computational results.