Redox-induced reversible intramolecular carbon-nitrogen bond formation of an azopyridylruthenium complex: Control of carbonyl ligand photoreactivity caused by structural change of the complex

A redox-induced intramolecular C-N bond was formed in an azopyridylruthenium complex with the terminal CO ligand. The reduction product was isolated and fully characterized. The reversible protection-deprotection of the CO moiety by redox reactions led to a large difference in photoreactivity of the coordinated carbonyl.