Room temperature phosphorescent triarylborane functionalized iridium complexes

Abstract

We report a series of room temperature phosphorescent compounds 1–6 composed of triarylborane (TAB) and cyclometallated iridium complexes. The optical characteristics such as energy of transition and luminescence quantum yield of these compounds can be conveniently fine-tuned by judiciously varying the cyclometallating ligand and the spacer between boron and iridium centers. Compounds 1–6 exhibit bright phosphorescence with the emission color ranging from green to red under a N₂ atmosphere. A maximum quantum yield of 0.95 was observed for complex 2. Complexes 1–6 exhibit a rare type of dual emission from singlet and triplet excited states under ambient conditions. The experimental observations are well supported by the theoretical calculations.