Metallic Axial Asymmetry in Dome ‐Like Iron Porphyrins Boosts Advanced Oxidation Processes: Implication of Allosteric Effect of Heme Peroxidases

The remarkable catalytic activity of heme enzymes originates from distinctive allosteric effects mediated by macrocyclic deformations. However, the role of dome ‐type deformation remains poorly understood. To elucidate this mechanism, we synthesized a series of 5,15‐monostrapped iron(III) porphyrins exhibiting dome ‐like deformation with precisely tunable ring distortions, serving as structural mimics of the dome conformation. These compounds were employed to catalyze the oxidative degradation of methylene blue (MB). The results demonstrate a strong correlation between catalytic efficiency and metallic axial asymmetry. Mechanistic studies reveal that this correlation stems from axial charge dismutation in the d _z ² orbital induced by the asymmetry, which facilitates peroxo bond cleavage to form two reactive oxygen species (ROS), thereby enhancing degradation energy. This study provides the first definitive mechanistic elucidation of heme dome deformation, offering crucial experimental insights into the heme cycle.