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Promoting Proton Transfer and Stabilizing Intermediates in Catalytic Water Oxidation via Hydrophobic Outer Sphere Interactions.

ABSTRACT: The outer coordination sphere of metalloenzyme often plays an important role in its high catalytic activity, however, this principle is rarely considered in the design of man-made molecular catalysts. Herein, four Ru-bda (bda=2,2'-bipyridine-6,6'-dicarboxylate) based molecular water oxidation catalysts with well-defined outer spheres are designed and synthesized. Experimental and theoretical studies showed that the hydrophobic environment around the Ru center could lead to thermodynamic stabilization of the high-valent intermediates and kinetic acceleration of the proton transfer process during catalytic water oxidation. By this outer sphere stabilization, a 6-fold rate increase for water oxidation catalysis has been achieved.

SUBMITTER: Liu T

PROVIDER: S-EPMC9314586 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Promoting Proton Transfer and Stabilizing Intermediates in Catalytic Water Oxidation via Hydrophobic Outer Sphere Interactions.

Liu Tianqi T Li Ge G Shen Nannan N Wang Linqin L Timmer Brian J J BJJ Kravchenko Alexander A Zhou Shengyang S Gao Ying Y Yang Yi Y Yang Hao H Xu Bo B Zhang Biaobiao B Ahlquist Mårten S G MSG Sun Licheng L

Chemistry (Weinheim an der Bergstrasse, Germany) 20220324 24

The outer coordination sphere of metalloenzyme often plays an important role in its high catalytic activity, however, this principle is rarely considered in the design of man-made molecular catalysts. Herein, four Ru-bda (bda=2,2'-bipyridine-6,6'-dicarboxylate) based molecular water oxidation catalysts with well-defined outer spheres are designed and synthesized. Experimental and theoretical studies showed that the hydrophobic environment around the Ru center could lead to thermodynamic stabiliz ...[more]

PMID: 35289447

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