Photoisomerization of ruthenium(II) aquo complexes: mechanistic insights and application development

Ruthenium(II) complexes with polypyridyl ligands have been extensively studied as promising functional molecules due to their unique photochemical and photophysical properties as well as redox properties. In this context, we report the photoisomerization of distal-[Ru(tpy)(pynp)OH2]2+ (d-1) (tpy = 2,2′;6′,2′′-terpyridine, pynp = 2-(2-pyridyl)-1,8-naphthyridine) to proximal-[Ru(tpy)(pynp)OH2]2+ (p-1), which has not been previously characterized for polypyridyl ruthenium(II) aquo complexes. Herein, we review recent progress made by our group on the mechanistic insights and application developments related to the photoisomerization of polypyridyl ruthenium(II) aquo complexes. We report a new strategic synthesis of dinuclear ruthenium(II) complexes that can act as an active water oxidation catalyst, as well as the development of unique visible-light-responsive giant vesicles, both of which were achieved based on photoisomerization.