Designing a binuclear copper center-incorporated photocatalyst to simulate enzyme catalysis in aerobic hydroxylation of phenylboronic acids

Abstract

Inspired by the catalytic processes of enzymes, we developed a multifunctional catalytic system with enzyme-like active centers and cofactors by means of the crystal engineering strategy. Herein, a new photoactive polyoxometalate-based metal–organic framework (POMOF), Cu(I)W–TPT, was synthesized through a solvothermal reaction. The densely distributed binuclear copper centers and strong π⋯π interactions within TPT moieties in the confined space of Cu(I)W–TPT ensure the charge transport processes. POMs can continuously accept electrons and inhibit the rapid recombination of photogenerated electron–hole pairs, resulting in efficient electron transfer through type I reactions and the generation of a single reactive oxygen species (ROS) ˙O₂⁻. Cu(I)W–TPT gave a high yield and excellent chemoselectivity in the oxidation of phenylboronic acid to phenol by the synergetic effect of each component under an air atmosphere and visible light irradiation for 24 h. ˙O₂⁻ is the main ROS in the highly selective formation of phenols through the aerobic oxidation of phenylboronic acid, effectively evading the overoxidation of phenols.