A Novel Class of Emitting Amorphous Molecular Materials with Bipolar Character for Electroluminescence

A novel class of color-tunable emitting amorphous molecular materials with desired bipolar character, 4-dimesitylboryl-N,N-bis(9,9-dimethylfluoren-2-yl)aniline (FlAMB-0T), 2-{4-[bis(9,9-dimethylfluoren-2-yl)amino]phenyl}-5-(dimesitylboryl)thiophene (FlAMB-1T), 2-{4-[bis(9,9-dimethylfluoren-2-yl)amino]phenyl}-2‘-dimesitylboryl-5,5‘-bithiophene (FlAMB-2T), and 5-{4-[bis(9,9-dimethylfluoren-2-yl)amino]phenyl}-5‘ ‘-dimesitylboryl-2,2‘:5‘,2‘ ‘-terthiophene (FlAMB-3T), have been designed and synthesized. This novel class of compounds is characterized by reversible anodic oxidation and cathodic reduction, intense fluorescence emission, and ready formation of stable amorphous glasses with high glass-transition temperatures above 120 °C. They function as excellent emitting materials for organic electroluminescent (EL) devices, emitting multicolor light including white. They also serve as good host materials for emissive dopants in organic EL devices, permitting color tuning and leading to higher performance.