Abstract
A series of novel boron complexes with electron deficient pyridyl pyrrolide and electron donating triphenylamine or phenylcarbazolyl fragment were synthesized. In this thesis, we strategically design the titled ligands such that the electron donor (HOMO) and acceptor (LUMO) moieties are spatially separated with orthogonal orientation. The slim orbital overlap between HOMO and LUMO leads to the close lying S1 and T1 states and thereby the generation of thermally activated delayed fluorescence (TADF). OLEDs using complex 2a processed by spin coating achieved an external quantum efficiency of 13.5%, demonstrating high performance boron-core based OLEDs via harvesting TADF.