Synthesis of new polyconjugated molecules with biphenyl, dibenzothiophene, carbazole and phenanthrene units

The simple methods of synthesis of hardly accessible substituted biphenyl, dibenzothiophene, carbazole and phenanthrene derivatives were elaborated starting from dimethyl 4,4’biphenyldicarboxylate. The series of new luminophores with extended π-conjugated chains based on combinations of biphenyl, carbazole, dibenzothiophene, phenanthrene fragments and alternating phenyl, vinyl or heterocyclic units were synthesized by the Wittig and the Knoevenagel reactions of corresponding aromatic dialdehydes and different CH-acids or phosphonium salts. Investigation of the effect of various substituents on the luminescent properties has been presented. The new luminophores could be used as emissive or charge transport layers in organic light emitting diodes (OLEDs).