Photo-/Electroinduced Irreversible Isomerization Of 2,2'-Azobispyridine Ligands In Arene Ruthenium(Ii) Complexes

Novel arene Ru-II complexes containing 2,2'-azobispyridine ligands were synthesized and characterized by using H-1 and C-13 NMR spectroscopy, UV/vis spectroscopy, electrochemistry, DFT calculations and single-crystal X-ray diffraction. Z-configured complexes featuring unprecedented seven-membered chelate rings involving the nitrogen atom of both pyridines were isolated and were shown to undergo irreversible isomerization to the corresponding E-configured five-membered chelate complexes in response to light or electrochemical stimulus.