[Ru(bpy)3]2+ Derivatives-Incorporated POM@MOFs with Good Photocatalytic Activity for Visible-Light-Driven Oxidative Coupling of Amines to Imines

Two novel POM@MOFs, {H₃Zn_2.5(H₂O)₁₀[Ru(dcbpy)₃][PMo₁₁^VIMo^VO₄₀]}·2H₂O (RuZn-PMo) and {H₃Ni_2.5(H₂O)₁₂[Ru(dcbpy)₃][PMo₁₁^VIMo^VO₄₀]}·5H₂O (RuNi-PMo), have been synthesized through a traditional hydrothermal method. They are composed of [Ru(bpy)₃]²⁺-derived hexa-carboxylate and Keggin-type anion [PMo₁₁^VIMo^VO₄₀]^4-. In addition, their structures were well characterized by various spectroscopic methods. Under the irradiation of visible light (λ > 400 nm), RuZn-PMo and RuNi-PMo as heterogeneous photocatalysts showed efficient photocatalytic performance in the coupling reaction of amines, with TONs of 451 and 454, respectively. Moreover, RuZn-PMo exhibited excellent reusability and stability after three continuous reaction cycles. Besides, EPR measurements were performed to elucidate the reaction mechanism.