Synthesis of conjugatedbridged triphenylenes and application in OLEDs

Novel conjugated-bridged triphenylene derivatives with electroluminescent properties were synthesized. A six step synthesis yields the cyanomethyltriphenylene derivatives (7a–7d). These were condensed by applying a Knoevenagel reaction with the alkoxy substituted dialdehyde 8 to PPV analogous short chain compounds 9a–9d. The products 9a–9d show bright orange to red photoluminescence. They are suitable as the emissive layer in organic light-emitting diodes (OLEDs), both in single and double layer arrangements with copper phthalocyanine as the hole transport layer.