Synthesis and studies on luminescent biphenyl compounds

A series of new soluble compounds based on a combination of biphenyl and stilbene structural elements having a low tendency to crystallize is described. Investigations on the effect of different substituents on the photoluminescence (PL) are presented. The new biphenyls are suitable as blue emissive layers in light emitting diodes (LEDs). In order to understand the mechanisms of light emission and to predict the influence of substitution on the emitted light, short-chain model compounds or well defined sections of poly para-phenylenevinylene (PPV) are synthesized. Many short-chain compounds are found suitable as emissive layers in organic LEDs, mostly emitting with green to red color.