Since photochemical CO2 reduction using long wavelength regions of sunlight is important, we have reported the first photochemical CO2 reduction with red visible light (>650 nm) by using a synthetic chlorophyll derivative covalently linked with a rhenium bipyridine complex. In the reported system, electron/energy transfer from the photoexcited chlorophyll to the catalytic Re complex was not so effective. To accelerate the process for achieving efficient photochemical reduction of CO2, we controlled the redox potential of Re complex and improved the chlorophyll donor by a simple modification. As a result, we achieved strong quenching of the excited states of a 131-deoxochlorophyll derivative with a rhenium bipyridine complex in a molecule.
2015 The Chemical Society of Japan