Recently, a research paper titled "Integrating Two Photochromics into One Three-Dimensional Covalent Organic Framework for Synergistically Enhancing Multiple Photocatalytic Oxidations" was published in the internationally renowned journal Angewandte Chemie International Edition by Professor Li Peizhou's group from the School of Chemistry and Chemical Engineering at Shandong University.

Nowadays, photocatalytic oxidation reactions play a crucial role in chemical synthesis, however, the development of effective photocatalysts is facing challenges. This study focuses on constructing a novel covalent organic framework (COF) for broad photocatalytic oxidation reactions. The research team successfully created a three-dimensional photoactive COF by rationally integrating porphyrin and triphenylamine photochromics.

Characterization studies indicated the formation of a crystalline and three-dimensional porous framework with effective photochemical semiconductor properties. Electron paramagnetic resonance (EPR) measurements showed that the COF can generate both singlet oxygen (¹O₂) and superoxide radical anions (·O₂⁻). Experimental and theoretical studies confirmed a synergistically enhanced efficiency in multiple photocatalytic reactions, such as the photocatalytic aerobic oxidation of alkylbenzenes, silanes, thioanisoles, and the cross-dehydrogenative coupling reaction of N-phenyltetrahydroisoquinoline and indole.

The research also explored the catalytic mechanisms of these reactions and found that the enhancement in photocatalytic activity is due to the synergistic effect of the two integrated reactants. Additionally, the COF demonstrated high catalytic activity towards a wide range of substrates, and its recyclability was also investigated, showing good stability after multiple catalytic cycles. These findings provide a new strategy for fabricating effective photocatalysts for broad applications.

This work was supported by the Shandong Provincial Natural Science Foundation and the Singapore Ministry of Education Academic Research Fund.