Synthesis of conjugated-bridged triphenylenes and application in OLEDs

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