Artificial [FeFe]‐Hydrogenase Mimics From Ferrocenyl Thioketone‐Functionalized Triphenylamine and (Bi)thiophene Derivatives: Synthesis, Characterization, and Hydrogen Evolution Catalysis

Thiocarbonyl compounds, especially thioketones, have emerged as promising precursors for constructing [FeFe]‐hydrogenase mimics that can mediate hydrogen evolution through both electrochemical and photocatalytic processes. In this work, we report the synthesis of ferrocenyl thioketone‐functionalized triphenylamine and triphenylamine‐(bi)thiophene derivatives as proligands for the assembly of artificial [FeFe]‐hydrogenase active site models. Structural and chemical features of the obtained complexes were elucidated through NMR and IR spectroscopy, elemental analysis, mass spectrometry, and single‐crystal X‐ray diffraction studies. Electrochemical studies using cyclic voltammetry revealed that these architectural mimics efficiently catalyze proton reduction to hydrogen in both the absence and presence of acetic acid (AcOH) as a proton source. Notably, the obtained complexes exhibit less negative reduction potentials than previously reported analogs, suggesting facilitated reduction and improved stabilization of the reduced species.