Synthesis of an Emissive Spectacle-Shaped Hexanuclear Rhenium(I) Complex.

Ring-shaped multinuclear Re(I) complexes (Re(I) rings) have the potential to function as useful units in multifarious photofunctional compounds because of their flexibility in molecular design and various photofunctions. The first synthetic example of the coupling reaction using a Re(I) ring as a building block to synthesize a novel spectacle-shaped hexanuclear complex is reported herein. This complex shows an efficient intramolecular energy transfer to accumulate the excitation energy into the central Re(I) units, and has suitable photophysical properties as a photosensitizer.