Furo[3,2‐ c ]pyridine‐Based Iridium Complex Containing two Methoxy Groups for Efficient Solution‐Processed Phosphorescent OLEDs

A furo[3,2‐ c ]pyridine‐based iridium complex, namely [(3,5‐diMeOpfupy) 2 Ir(acac)], has been designed and synthesized by introducing two methoxy groups at the 3‐ and 5‐positions of a phenyl ring. Such a small structure variation of the C^N ligand can not only avoid isomer production to favor easy purification, but also improve the solubility to ensure low‐cost wet methods. Similar to the model complex [(3‐MeOpfupy) 2 Ir(acac)] containing one methoxy group, [(3,5‐diMeOpfupy) 2 Ir(acac)] possesses an orange emission peak at 598 nm together with a photoluminescence quantum yield (PLQY) of 0.32 and an exciton lifetime of 1.29 μs. The corresponding solution‐processed devices realize a maximum current efficiency of 17.2 cd/A (18.5 lm/W, 8.9 %) as well as Commission Internationale de L'Eclairage (CIE) coordinates of (0.60, 0.39). The result indicates that the multiple methoxy modification is a promising strategy towards isomer‐free and solution‐processable furo[3,2‐c]pyridine‐based iridium complexes.