Synthesis and characterisation of binuclear cyclopalladated p-alkoxyphenylazo complexes: preparation of new mesogenic materials

In order to investigate new materials with liquid-crystalline properties, the synthesis, characterisation, and thermal behaviour of binuclear complexes of PdII with p-alkoxyphenylazobenzene ligands are reported. Whilst none of the free ligands displays ordered mesophases, some of their cyclopalladated derivatives show smectic phases at temperatures below 130 °C. Possible explanations of the function of the metal–halide bridge in determining the mesomorphism are provided.