Highly Efficient Red Phosphorescent Osmium(II) Complexes for OLED Applications

The nonionic, red-emitting complexes [Os(fppz)2L2] (L = PPh2Me (1), PPhMe2 (2)) and [Os(bptz)2L2] (L = PPh2Me (3)) were synthesized, showing highly intense red phosphorescent emission in CH2Cl2 solution at λmax 617, 632, and 649 nm, respectively. The electroluminescent properties of these compounds on OLEDs showed promising device efficiencies required for future OLED applications.