Abstract: The control of the second coordination sphere in a coordination complex plays an important role in improving catalytic efficiency. Higher coordination spheres can also be utilized to improve catalysis by imitating nature.

Here we report a series of porphyrin complexes with modification using distinct geometries of triazole units the second coordination sphere and PEG chains in the higher functional spheres of the ligand scaffold. Our findings suggest that the triazole units function cooperatively to stabilize the bound substrate in order to facilitate intramolecular proton transfer and that PEG chains enhance catalytic efficiency in proton-coupled electron transfer reactions by forming proton shuttles.