Photofunctional multinuclear rhenium(I) diimine carbonyl complexes
This account looks comprehensively at the syntheses, photophysical properties and applications of structurally diverse, multinuclear coordination compounds that embed a Re(I)-diimine-carbonyl moiety. Different types of linkages in terms of configuration and proper bridging lead to several types of discrete linear or cyclic macromolecular aggregates with different sizes, which consequently have a significant effect on their properties. The Re-backbone in the multinuclear assembly may have only a structural role and mainly exhibits host–guest behaviour for encapsulation, or it may produce photofunctional properties as a direct result of the Re(I) chromophoric unit, which makes these compounds applicable in light-harvesting systems or photochemical CO2 reduction. In particular, we would like to emphasize bisphosphine-bridged multinuclear complexes that exhibit outstanding photophysical properties.