Synthesis of a crowned azobenzene liquid crystal and its application to thermoresponsive ion-conducting films

Two azobenzene derivatives carrying benzo-15-crown-5 or benzo-18-crown-6 moiety have been synthesized. One of the crowned azobenzene derivatives, 2,3-[4-(4-octylphenylazo)phenyloxycarbonyl]benzo-1,4,7,10,13-pentaoxacyclopentadeca-2-ene, was found to be a monotropic liquid-crystalline compound and the other did not show any liquid-crystalline phase. Incorporation of the benzo-15-crown-5-containing azobenzene derivative into an ionically conducting composite film produced bistable ionic conductivities, which reflected the liquid-crystalline characteristics.