Synthesis of novel bithiophene derivatives with an organosilanylene bridge, and their applications to electron-transporting materials in EL devices

Compounds having two bithiophene units linked by an organosilicon bridge were prepared. Their UV spectra and cyclic voltammograms indicated that the compounds have the low-lying LUMO. The electron transporting properties of the present silicon-bridged bithiophene derivatives were evaluated by the performance of electroluminescent (EL) devices having vapor deposited silicon-bridged bithiophenes, Alq, and TPD layers, as the electron-transport, emitter and hole-transport, respectively. By applying the bias voltage on the devices, the devices emitted green EL originated from the Alq emission with the maximum luminance of 8500 cd m−2.