Synthesis of π-Conjugated polymers containing fluorinated arylene units via direct arylation: Efficient synthetic method of materials for oleds

摘要

Polycondensation via direct arylation of tetrafluorobenzene or octafluorobiphenyl was investigated for the synthesis of π-conjugated polymers consisting of fluorinated arylene units. The optimization of reaction conditions revealed that a combination of Pd(OAc) _2 and P ~tBu _2Me-HBF _4 is the most efficient catalytic system for the polycondensation reactions. The polycondensation reactions produced four types of π-conjugated polymers having low highest occupied molecular orbital (HOMO) levels due to the strong electron-withdrawing nature of the fluorine substituents. Owing to the low HOMO levels, the synthesized polymers served as an efficient hole-blocking layer (HBL) in OLEDs.