Synthesis and Electro-Optical Properties of 9,10-Substituted Anthracene Derivatives for Flexible OLED Devices

Abstract

A silylated anthracene derivative, bis[2-(p-trimethylsilyl)phenylethynyl]anthracene (1), was synthesized by using Sonogashira reaction. Compound 1 showed two absorption maxia(lambda(max, abs)) at 444 and 447 nm, and fluorescence maximum (lambda(max, em)) at 478 nm. Compound 1 had higher melting temperature of 274 degrees C compared to anthracene 210 degrees C presumably due to confinement of pi-conjugated system by trimethylsilyl end-capping, which will be beneficial in the high temperature operation condition of OLED devices. As compared to the commercially available, blue-light emitting, material 4 and tert-butylated compound 2, the compound 1 showed small red-shift of 9 nm in the OLED emission from the by PL lambda(max) due to the increased electron density in the anthracene ring. The compound 1 was also found to be easily fabricated in the flexible OLED devices and showed a low threshold voltage and high current efficiency compared with other anthracene derivatives