Synthesis and characterization of an efficient solution-processable green Ir(III) complex with a solubilizing group using a tandem reaction

The new efficient green heteroleptic phosphorescent Ir(III) complex [5-methyl-8-trifluoromethyl-5H-benzo(c)(1,5)naphthyridin-6-one](3-(2-ethoxyethoxypyraznate))iridium(III) (Ir-prz) was designed and synthesized with a high photoluminescence quantum yield (PLQY). In addition, the solubilizing group 2-ethoxyethanol (EO2-) was attached to the ancillary ligand via a tandem reaction. Their thermal, photophysical, electrochemical, and electroluminescent (EL) properties were fully investigated. The solution-processed green PHOLED using Ir-prz as dopant and 4,4′-bis(N-carbazolyl)-1,1′-biphenyl as host achieved a maximum external quantum efficiency of 8.94% and a maximum current efficiency of 16.50 cd A−1, with a maximum luminescence of 18,638 cd m−2.