Metal-Free Activation of Molecular Oxygen by 9-Fluorenone-Based Porous Organic Polymers for Selective Aerobic Oxidation.

Oxygen activation is a critical step in heterogeneous oxidative processes, particularly in catalytic, electrolytic, and pharmaceutical applications. Among the various catalysts available for photocatalytic O2 activation, homogeneous aryl ketones are at the forefront. To avoid the degradation and deactivation of aryl ketones, 9-fluorenone-based porous organic polymers were designed and regulated by doping them with co-monomers. The obtained heterogeneous photocatalyst showed good performance in O2 activation, and its performance was better than that of homogeneous 9-fluorenone. The obtained heterogeneous photocatalyst showed good reusability. We believe that the presented method and findings represent an important step toward designing catalysts tailored for specific tasks.

Hydrogenation of levulinic acid to γ-valerolactone over hydrophobic Ru@HCP catalysts.

This study introduces an efficient strategy for promoting the synthesis of γ-valerolactone (GVL) via levulinic acid (LA) hydrogenation. A series of hyper-crosslinked porous polymer (HCP) supported Ru catalysts with different monomers were prepared. The wettabilities were controlled by the surface functional groups. The hydrophobic catalysts showed much higher activity than the hydrophilic ones in the hydrogenation of LA to GVL, highly possible due to the substrate enrichment. Further insight showed that the reaction proceeded through the 4-HVA route. These results illustrated the importance of surface wettability in bio-based molecule upgrading, which is beneficial for catalyst design.