Photoactive Heterometallic Assemblies Based on Dinuclear Clathrochelate Metalloligands and a ZnII–Porphyrin/RuII–Metallacycle

Abstract A modular self-assembly strategy combining a RuII-metallacycle of ZnII-porphyrins with three different dinuclear boron-capped clathrochelate metalloligands bearing two hexacoordinate metal ions in the center (either ZnII/ZnII or mixed-valence FeII/FeIII cores) affords a new family of discrete photoactive heterometallic sandwich-like assemblies. The assemblies are formed quantitatively in solution and fully characterized by UV–Vis, IR, and NMR spectroscopy, DOSY, and single-crystal X-ray diffraction. The nature of the intercomponent photoinduced process depends critically on the identity of the clathrochelate connector: in the ZnII/ZnII-containing assembly, excitation of the clathrochelate unit results in quantitative energy transfer to the ZnII-porphyrin platform; in the FeII/FeIII-containing assembly, the ZnII-porphyrin singlet excited state is completely quenched by the mixed-valence iron core. These results demonstrate that the photoinduced intercomponent process can be switched simply by varying the metal identity within the clathrochelate connector, while retaining the same overall supramolecular architecture, offering a new design principle for photoactive multicomponent inorganic assemblies.