Heterogeneous Polyoxometalate-Based Catalysts for Functionalized Quinones Synthesis: Systematic Advances, Prospects, and Challenges.

Functionalized quinones are crucial structural building blocks for synthesizing significant biologically active compounds. The selective catalytic oxidation of low-valent oxygen precursors (including aromatic compounds, phenolic derivatives, and hydroquinone analogs) has been widely recognized as one of the most economically and environmentally favorable approaches for producing functionalized quinones. Polyoxometalates (POMs), as versatile inorganic clusters, have attracted much attention in multidisciplinary fields, especially in catalysis, due to their adjustable structural configuration and acid-base properties, excellent redox properties, as well as remarkable thermal stability, chemical stability, and hydrolysis stability. As a pivotal branch, POM-based heterogeneous catalytic systems not only preserve the inherent, highly active sites of POMs but also establish synergistic catalytic networks through the integration of hybrid components. This paves a new way for achieving material recyclability and green catalytic technology. This review presents a critical analysis of research advances in POM-based heterogeneous catalysts for quinone synthesis over recent decades and systematically proposes optimization strategies from the perspective of material design principles and catalytic processes, aiming to offer molecular engineering theoretical support for the construction of a new generation of catalytic platform.