Synthesis of Redox‐switchable 5,15‐Dialkyl‐10,20‐diaryl‐5,15‐diazaporphyrins and Diversification of their N ‐Alkyl Groups

Nickel(II) and copper(II) complexes of redox‐switchable 20π, 19π, and 18π 5,15‐dialkyl‐10,20‐diaryl‐5,15‐diazaporphyrins were prepared through a metal‐templated cyclization method. Furthermore, the terminal silyloxy groups in the peripheral N ‐alkyl chains were transformed into hydroxy groups by deprotection. It is worth noting that redox reactions between the 19π and 18π systems bearing hydroxy groups caused a change in the water solubility of the diazaporphyrin chromophore.