Derivatives of 2,7-dibromo-9,9-dimethyl-9h-fluorene and 2,7-dibromo-9,9-spirobifluorene as electroactive materials /

Low-molar-mass and polymer organic light emitting diodes have attracted considerable attention due to their great application potential in large area flat panel displays and solid state lighting [1 ]. Such devices tend to have multilayer device configuration with a hole transport layer, an electron transport layer and an emissive layer, and some of them also have a hole injection and an electron injection layer [2]. The selection of appropriate materials for each layer is of great importance. Generally, the molecular structures of hole transport materials usually contain electron-donating moieties, such as carbazole, triarylamine, diphenylamine, N-phenyl-1-naphthylamine etc. [3]. However, traditional methods for synthesizing electroactive materials have notable drawbacks such as low reaction yields, longer reaction times, dependence on hazardous, expensive and moisture-sensitive reagents, as well as involving large amounts of reactants. Additionaly, these methods often require intense reaction conditions, longer workup procedures, and difficulties in catalyst regeneration. In this work, we employed efficient Suzuki coupling reactions of 2,7-dibromo-9,9-dimethyl-9H-fluorene and 2,7-dibromo-9,9’-spirobifluorene with (B-(9-phenyl-9H-carbazol-3-yl)-boronic acid and (6-Phenyldibenzo[b,d]furan-4-yl)boronic acid. Their thermal, electrochemical, and photophysical properties will be presented.