Ferrocenyl‐Capped p ‐Phenylenediamine as a Redox‐Switching System

Terminal redox‐active ferrocenyl groups were introduced into the redox‐active p ‐phenylenediamine bridging spacer, which can be oxidized to the p ‐quinonediimine, to provide a redox‐switching system with electronic communication between the ferrocenyl groups through the redox‐active π‐conjugated bridging spacer. The communication was controlled by redox interconversion between the p ‐phenylenediamine and p ‐quinonediimine spacers. Furthermore, two palladium complexes were demonstrated to be introduced to the oxidized quinonediimine moiety, affording the multimetallic complex, in which the complexed quinonediimine serves as an electron sink. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)