Palladacycle-Catalyzed Triple Suzuki Coupling Strategy for the Synthesis of Anthracene-Based OLED Emitters.

The development of the site-selective Suzuki-Miyaura cross-coupling of dibromoanthracene as an efficient strategy toward organic light emitting diodes (OLEDs) is disclosed in this article. An unprecedented step-economic palladacycle-promoted triple Suzuki coupling protocol allowed the synthesis of three new OLED emitters and could prove to be a useful general strategy for researchers working in this field. Characterization of the synthesized molecules by UV-vis spectroscopy and thermogravimetric analysis-differential scanning calorimetry followed by density functional theory studies of the different properties strongly confirms the derivatives possess more significant hole mobility character than electron transfer capability.

[Pd(C

Direct transmetallation between palladacyclic complexes and arylboronic acid occurs to give isolable transmetallation products. In THF, the reaction occurs <0.5 h. Prolonged reaction leads to the generation of a dinuclear Pd complex bearing bridging µ-hydroxo and µ-acetoxy ligands. Insight into precatalyst activation for Suzuki-Miyaura cross-couplings mediated by palladacycles has been gained, where acetate and N-imidate anions activate a neutral arylboronic acid.