Near‐IR Phosphorescent Ruthenium(II) and Iridium(III) Perylene Bisimide Metal Complexes

Abstract The phosphorescence emission of perylene bisimide derivatives has been rarely reported. Two novel ruthenium(II) and iridium(III) complexes of an azabenz‐annulated perylene bisimide (ab‐PBI), Ru(bpy) 2 (ab‐PBI)PF 6 2 1 and Cp*Ir(ab‐PBI)ClPF 6 2 are now presented that both show NIR phosphorescence between 750–1000 nm in solution at room temperature. For an NIR emitter, the ruthenium complex 1 displays an unusually high quantum yield ( Φ p ) of 11 % with a lifetime ( τ p ) of 4.2 μs, while iridium complex 2 exhibits Φ p <1 % and τ p =33 μs. 1 and 2 are the first PBI‐metal complexes in which the spin–orbit coupling is strong enough to facilitate not only the S n →T n intersystem crossing of the PBI dye, but also the radiative T 1 →S 0 transition, that is, phosphorescence.