Neighbouring effects on catalytic epoxidation by Fe-cyclam in M₂-PDIxCy complexes

The unsymmetric PDIeCy ligand, featuring pyridinediimine and cylam sites, can be selectively metalated. Complementing the diiron compound, we have synthesized two heterobimetallic isomers, [ZnPDIFeCy(PDIeCy)(OTf)4] (3) and [FePDIZnCy(PDIeCy)(OTf)4] (4), and a dizinc complex, [Zn2(PDIeCy)(OTf)4] (5). Olefin epoxidation by the series of complexes was investigated. The M-PDI site influences the reactivity of the M-cyclam, resulting in increased activity toward enones.