Ru Metalloligands Participate in the Construction of POM@MOF for Enhancing the Visible Photoinduced Baeyer-Villiger Oxidation Reaction.

Directed synthesis of high-efficiency visible photoinduced Baeyer-Villiger oxidation catalysts is of primary significance. Here, the isopolymolybdate anion [β-MoO] is for the first time encapsulated with the photosensitive metalloligand [Ru(bpy)(Hdcbpy)] (bpy = 2,2'-bipyridine; Hdcbpy = 2,2'-bipyridine-5,5'-dicarboxylic acid) to synthesize polyoxometalate@metal-organic frameworks, {(CdDMF)Ru(bpy)(dcbpy)}·5DMF (Ru-Mo). The composite photocatalyst Ru-Mo not only has a light absorption of 700 nm but also shortens the photogenerated electron transfer distances and accelerates charge and proton transfer. Ru-Mo can perform the Baeyer-Villiger oxidation with high selectivity and up to 96.7% yield under visible light (λ > 400 nm) irradiation. The turnover number and turnover frequency of the reaction were computed to be 967 and 548 h, respectively, and the apparent quantum yield was 6.84% by 425 nm. Simultaneously, the radical mechanism of Baeyer-Villiger oxidation of Ru-Mo in the O/benzaldehyde system under visible light (λ > 400 nm) irradiation was proposed.