1,3-Bis[5-(dimesitylboryl)thiophen-2-yl]benzene and 1,3,5-tris[5-(dimesitylboryl)thiophen-2-yl]benzene as a novel family of electron-transporting hole blockers for organic electroluminescent devices

A novel family of electron-transporting hole blockers, 1,3-bis[5-(dimesityl boryl)thiophen-2-yl]benz and 1,3,5-tris[5(dimesitylboryl)thiophen-2-yl]benz ene (TMB-TB), were designed and synthesized. They were found to exhibit mul tiple redox behavior in electrochemical reduction and to readily form stabl e amorphous glasses with high glass-transition temperatures above 100 degre esC. TMB-TB was proven to function well as a hole blocker in blue-emitting organic electroluminescent devices.