Synthesis of the first homobimetallic thiazole–ferrocene ligand displaying metal–metal interaction and redox-switchable proton affinity

The previously unreported 2,5-bis(ferrocenyl)thiazole 4, prepared from α-aminoacetylferrocene and chlorocarbonylferrocene in two steps, exhibits two reversible redox processes, indicating a significant electronic interaction between the iron centres. Electrochemical investigation of the protonated ligand revealed a reversible electrochemically-driven deprotonation/reprotonation process.